<^ 


J 


8061  'u  m  -m 
'A  'N  'asnoBjAs 

SJ931EM 

so-ig  pioiX^f) 
)unouJO)04d 


r.v.' 

m 


\^ 


SOME  WELL-KNOWN 

MENTAL  TESTS  EVALUATED 

AND  COMPARED 


BY 
DOROTHY  RUTH  MORGENTHAU 


Submitted  in  partial  fulfillment  of  the  requirements  for  the 

degree  of  Doctor  of  Philosophy,  in  the  Faculty  of 

Philosophy,!  Columbia  University 


t 


REPRINTED  FROM 

ARCHIVES  OF  PSYCHOLOGY 

R.  S.  WOODWORTH,  Editob 

No.  52 


NEW  YORK 

May,  1982 


SOME  WELL-KNOWN 

MENTAL  TESTS  EVALUATED 

AND  COMPARED 

BY 
DOROTHY  RUTH  MORGENTHAU 


Submitted  in  partial  fulfillment  of  the  requirements  for  the 

degree  of  Doctor  of  Philosophy,  in  the  Faculty  of 

Philosophy,  Columbia  University 


REPRINTED  FROM 

ARCHIVES  OF  PSYCHOLOGY 

No.  52 


NEW  YORK 
Mat,  1922 


v\ 


cxcHAr^u^ 


TABLE  OF  CONTENTS 

Introduction  5 

Subjects  8 

Tests  Briefly  Described  and  Reasons  for  Their  Selection       14 

Method — Applying  Tests  to  Subjects  21 

General  Considerations 

Specific  Observations  on  the  Application  of  the  Test 
Selected 

Results  25 

Conclusion  52 


507 7G3 


ACKNOWLEDGMENT. 

For  the  advice  of  Professor  Edward  Lee  Thorndike  of 
Teachers  College,  Columbia  University,  and  of  Dr.  William 
Healy  and  Dr.  Augusta  Bronner  of  Judge  Baker  Foundation, 
Boston,  the  v^riter  wishes  to  express  appreciation.  Special 
thanks  are  due  for  the  painstaking  assistance  given  by  Pro- 
fessor Robert  S.  Woodworth  of  Columbia  University,  New 
York  City. 


Some  Weil-Known  Mental  Tests 
Evaluated  and  Compared 

ONE  who  approaches  the  subject  of  the  measuring  of 
children's  mentality  will  find  that  the  mind  of  the  nor- 
mal child  has  received  attention  in  what  we  may  call 
vertical  and  parallel  respects.  There  have  been  a  considerable 
number  of  tests  developed  by  students  of  psychology  in  the  en- 
deavor to  secure  mental  measurements  independent  of  the 
experience  and  judgment  of  the  clinician.  The  development 
has  been  in  a  vertical  manner,  that  is,  the  best  recognized 
psychologists  who  have  undertaken  this  work  have  each  de- 
veloped tests,  have  each  put  them  into  extensive  practice  and 
have  published  the  results  of  that  experience.  But  each  of 
these  psychologists  has  developed  his  test  on  his  own  suppo- 
sitions, and,  basing  the  nature  of  his  test  on  his  own  experi- 
ence, has  tried  to  evolve  a  plan  of  testing  which  is  supposed  to 
be  useful  in  determining  mental  conditions  of  such  general  ex- 
tent that  they  may  roughly  be  called  intelligence.  Thus  we 
have  the  Stanf  ord-Binet  scale,  the  most  generally  used  of  any 
one  of  the  mental  tests.  Then  there  are  the  Porteus  tests,  the 
Pintner-Patterson  performance  scale,  and  a  dozen  or  more  of 
others  which  are  known  to  every  clinical  psychologist. 

The  development  of  mental  tests  has  been  parallel  in  that 
none  of  these  psychologists  in  developing  their  own  ideas 
have  carried  them  to  the  point  of  thoroughly  comparing  the  re- 
sults obtained  by  their  tests  to  the  results  obtained  by  the 
simultaneous  use  of  a  number  of  the  other  tests  all  with  re- 
spect to  normal  children.  There  has  been  some  comparison  of 
results  of  the  various  tests  when  applied  to  abnormal  children 
but  this  has  not  been  thoroughgoing  and  has  been  done  not  by 
making  the  tests  with  the  idea  of  eventually  combining  the  re- 
sults and  of  placing  valuations  upon  them,  but  merely  in  the 
course  of  clinical  work  with  abnormal  children.  It  is  question- 
able whether  such  results  are  sufi»  "icntly  thorough  to  be  con- 
sidered the  basis  for  a  convincing  answer  as  to  the  relative 
value  of  the  respective  tests,  and  inasmuch  as  they  were  made 
on  abnormal  minds,  one  would  not  dare  to  trust  even  those 


:6'  -'  '•':  ''"'''-■'  ^OME  WELL-KNOWN  MENTAL  TESTS 

comparative  results  with  respect  to  what  the  test  will  show  as 
to  normal  minds. 

Those  who  have  developed  their  respective  tests  have  com- 
pared them  with  some  other  mental  test,  most  frequently  one  of 
the  Binet  revisions.  But,  no  considerable  number  of  the  tests 
which  have  been  so  developed  in  parallel  fashion  have  been  ap- 
plied purposely  to  obtain  comparative  results  and  to  ascertain 
which  if  any  of  them  can  be  shown  to  be  untrustworthy  and 
what  group  of  them  can  be  relied  upon  as  furnishing  a  satis- 
factory schedule  for  testing  and  comparing  the  common  ele- 
ments of  mentality  in  normal  children. 

Upon  perceiving  that  there  was  a  lack  of  any  purposely 
made  comparative  study  of  mental  tests  it  was  proposed  here- 
in to  set  forth  the  results  of  such  a  study  of  about  a  dozen  of 
the  most  commonly  used  mental  tests.  The  tests  were  applied 
to  a  large  number  of  unselected  normal  children,  in  general 
each  child  receiving  the  full  schedule  of  tests.  By  means  of  the 
results  to  be  obtained  from  this  comparative  study  it  was  an- 
ticipated : 

1.  That  the  degree  of  reliability  of  each  test  would  be  indi- 
cated. 

2.  That  the  same  purposes  could  be  effected  with  respect  to 
the  value  of  each  test. 

3.  That  the  information  obtained  under  the  first  and  sec- 
ond headings  would  make  it  possible  to  select  a  schedule  of 
tests  of  indicated  reliability  for  application  to  normal  minds, 
or  further,  whether  the  Stanf ord-Binet  alone  would  suffice. 

4.  That  by  restricting  the  ages  of  children  tested  in  general 
to  from  ten  to  sixteen  years,  the  period  in  which  individual 
capacities  first  assume  importance  for  vocational  determina- 
tion, it  would  be  possible  to  guide  the  vocational  training  with 
some  degree  of  success. 

A  brief  statement  of  the  results  can  now  be  given  reserving 
the  more  detailed  statement  involving  the  basis  and  methods 
for  the  results  for  future  pages.  The  first  aim,  to  secure  an 
estimate  of  the  reliability  of  the  tests  used,  was  largely  suc- 
cessful. Of  the  thirteen  tests,  the  reliability  of  which  was 
investigated,  one  class,  the  four  construction  tests,  Healy  A 
and  B.  and  Knox  Moron  tests,  and  diamond  shaped  frame,  were 
found  to  be  unreliable ;  five  other  tests  were  found  to  be  relia- 
ble, namely  the  Stanford-Binet,  Pintner  Non-Language  group 
test,  Thorndike  Reading  Scale  Alpha  2,  Porteus  Maze  test,  and 


EVALUATED  AND  COMPARED  7 

Tapping  test;  while  the  reliability  of  four  tests,  the  Myers 
Mental  Measure,  Healy  Pictorial  Completion  test  II,  Healy- 
Bronner  learning  tests,  and  the  Crossline  test  was  undeter- 
mined for  various  reasons. 

The  results  obtained  as  to  value  of  the  tests  were  as  follows : 
Stanford-Binet,  Pintner,  Alpha  II,  and  Porteus  are  valuable 
tests  and  should  be  included  in  individual  case  studies.  In 
spite  of  their  unmeasured  reliability,  Myers  and  Pictorial 
Completion  II  are  also  valuable  tests  and  should  likewise  be 
included.  Judgment  should  be  suspended  with  regard  to 
learning  tests.  The  Tapping  test  is  of  doubtful,  value  and  its 
use  should  be  left  to  the  discretion  of  the  examiner.  The  Con- 
struction tests  because  of  their  unreliable  character  do  not 
give  valuable  results. 

As  to  the  schedule  of  tests  to  be  used  in  testing  normal  minds 
it  was  found  best  not  to  use  the  Stanford-Binet  alone  but  to 
have  the  schedule  composed  of  that  test  and  the  five  others 
which  were  found  valuable.  From  the  tests  used  and  results 
obtained  it  cannot  be  stated  here  whether  this  schedule  is  of 
value  as  to  vocational  guidance  for  the  reason  that  the  factors 
involved  in  each  test  are  not  known  with  certainty  and  until 
they  are  known,  definite  valid  conclusions  about  the  abilities 
of  the  individuals  concerned  cannot  be  reached. 


SUBJECTS. 

It  was  desired  to  test  one  hundred  normal  but  otherwise  un- 
selected  children.  In  order  to  obtain  an  unselected  group  it 
proved  necessary  to  select  the  subjects  very  carefully,  for,  if 
all  the  children  tested  had  been  from  a  Children's  Home,  or 
from  a  Settlement,  or  from  any  one  school,  the  result  would 
have  been  a  highly  selected  group.  To  avoid  this  a  few  were 
taken  from  many  different  sources  and  in  this  respect  the  dis- 
tribution proved  to  be  reasonably  satisfactory. 

As  to  age,  originally  the  plan  was  to  have  about  ten  children 
at  each  of  the  ten  periods  of  one  year  each,  from  seven  to  six- 
teen inclusive.  But  this  plan  was  given  up  because  our  inter- 
est is  not  with  the  six  or  seven  year  old  who  has  to  go  to  school 
and  learn  fundamentals,  no  matter  wherein  his  is  gifted  and 
who  rarely  shows  talents  or  handicaps  at  such  an  early  age. 
Our  chief  concern  is  with  children  in  the  sixth,  seventh  or 
eighth  grades  and  in  high  school,  because  they  are  the  adjust- 
ment problems,  and  because  it  is  important  to  aid  them  if  pos- 
sible in  deciding  whether  they  should  remain  in  school  or  go 
to  work.  If  the  latter  what  should  they  do,  if  the  former  what 
sort  of  training  do  they  need?  So  the  attempt  was  made  to 
lay  all  the  emphasis  here  and  reduce  the  number  of  children 
under  eleven  to  a  minimum.  Another  objection  to  the  origin- 
al plan  is  that  ten  in  a  group  is  too  small  for  any  kind  of  gen- 
eralization. 

The  total  number  tested  was  128,  of  which  116  usable  rec- 
ords were  retained.  For  various  reasons  many  of  these  rec- 
ords are  incomplete  so  that  this  number  was  necessary  in  or- 
der to  have  a  minimum  of  100  scores  on  each  test.  There  still 
remain  some  tests  which  were  given  to  less  than  100  children, 
but  the  number  is  in  each  case  sufficiently  large  to  give  valu- 
able results. 

All  defectives  were  excluded,  for  in  mixing  their  records 
with  those  of  normal  children  many  confusions  would  have 
arisen,  and  the  issues  would  have  been  less  clear.  Much  in- 
tensive work  has  been  done  in  testing  defectives,  so  that  we 
kr;cw  a  great  deal  about  their  reactions  to  a  group  of  tests 
such  as  we  have  chosen.  To  be  sure,  they  vary  considerably  in 
their  results,  but  we  know  in  general  the  points  where  they  are 
weakest  as  in  abstract  reasoning  and  formal  generalization, 

8 


EVALUATED  AND  COMPARED  9 

and  also  the  points  in  which  proportionately  they  excel.  By 
narrowing  the  field  to  normals  the  significance  of  the  conclu- 
sions can  be  made  more  pertinent.  This  was  an  arbitrary  pro- 
cedure dependent  largely  upon  the  judgment  of  the  writer,  and 
subject  to  criticism  on  this  basis.  It  is  quite  possible  that  some 
very  dull  normals  were  also  excluded,  this  being  justified  on 
the  grounds  that  their  normality  might  reasonably  have  been 
called  in  question  by  more  severe  examiners,  With  reference 
to  the  three  cases  whose  I.  Q.'s  fall  below  80,  there  seems  to 
be  no  doubt  that  they  are  to  be  considered  as  dull  normals. 
The  grade  they  attained  in  school  for  their  age,  their  response 
on  the  other  tests  and  their  behavior  in  the  community  all 
argue  for  including  them  in  our  study.  The  boy  receiving  the 
lowest  I.  Q. — 73 — was  born  in  the  United  States  but;  taken  to 
Italy  at  the  age  of  five,  and  remained  there  six  years.  In  spite 
of  this  he  was  in  the  eighth  grade.  He  did  very  well  with  all 
the  construction  tests. 

As  no  limitations  were  set  at  the  other  end,  the  grade  and  I. 
Q.  distributions  are  higher  than  one  would  otherwise  expect 
in  a  general  sampling  of  the  population. 

I.  Thirty-seven  children,  twelve  girls  and  twenty-five  boys, 
were  tested  at  the  Home  for  Jewish  Children  in  Dorchester, 
Massachusetts.  Many  of  these  children  were  half  orphans, 
some  had  lost  both  parents — most  of  them  were  in  the  Home 
temporarily.  They  were  chosen  from  the  total  number  entire- 
ly by  chance.  They  all  attended  public  school  in  the  vicinity 
and  all  but  two  or  three  had  come  to  the  Home  within  two 
years.  All  were  able  to  speak  and  understand  English,  this 
being  the  only  language  used  at  the  institution,  although  in 
many  of  their  homes  no  English  was  spoken.  Their  ages 
ranged  from  7-0  to  15-1. 

II.  Twenty-four  girls  came  from  Frances  Willard  Settle- 
ment in  Boston,  Massachusetts.  These  were  divided  into  three 
clubs — one  consisting  of  one  seventh  grade  and  ten  eighth 
grade  girls,  the  youngest  being  12-7  and  the  oldest  14-2.  They 
came  one  evening  a  week  for  the  express  purpose  of  taking 
the  tests.  They  were  the  first  ones  to  volunteer  from  a  large 
group.  The  other  two  groups  of  seven  and  six  respectively 
were  younger  girls  who  happened  to  meet  on  afternoons  which 
were  convenient  for  the  examiner. 

III.  Six  high  school  girls  in  New  York  volunteered  to  take 
the  tests. 


10 


SOME  WELL-KNOWN  MENTAL  TESTS 


IV.  The  ninth  grade  consisting  of  six  boys  and  five  girls  in 
the  Woodmere  School  (private)  at  Woodmere,  Long  Island, 
were  tested.    The  ages  ranged  from  13-1  to  15-2. 

V.  The  poorer  section  of  the  8B  class  of  Public  School  11, 
New  York,  were  tested.  There  were  thirty  boys  in  the  class 
ranging  in  age  from  13-2  to  16-11. 

VI.  Finally  eight  miscellaneous  children  were  tested. 

The  subjects  selected  appeared  to  give  a  satisfactory  differ- 
ence in  quality  so  as  to  bring  out  the  capacities  of  the  tests  to 
meet  a  variety  of  normal  mental  conditions. 


Yrs. 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 

7 

8 

8 

8 

8 

8 

8 

8 

8 

8 

8 

8 

8 

9 

9 

9 

9 

9 

9 

9 

9 

9 

9 

9 

9 
10 
10 
10 
10 


Mos. 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 
10 
11 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 
10 
11 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 
10 
11 

0 

1 

2 

3 


TABLE 
Frequency 
1 
0 
0 
0 
0 
0 
1 
0 
0 
0 
1 

0  3 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 

1 

1  2 

1 

0 

1 

0 

1 

0 

0 

2 

1 

1 

1 

0       8 

0 

0 

0 

2 

15 


I      AGE   DISTRIBUTION    116 

Yrs.  Mos.  Frequency 
4 
5 


CASES 


10 
10 
10 
10 
10 
10 
10 
10 

11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 

12 

12 
12 
12 
12 
12 
12 
12 
12 
12 
12 
12 


6 
7 
8 
9 
10 
11 

0 
1 
2 
3 

4 
5 
6 
7 
8 
9 
10 
11 

0 
1 
2 
3 

4 
5 
6 
7 
8 
9 
10 
11 


10 


21 


13 

0 

1 

13 

1 

2 

13 

2 

1 

13 

3 

0 

13 

4 

0 

13 

5 

3 

13 

6 

1 

13 

7 

1 

44 

Yrs. 
13 
13 
13 
13 
14 
14 
14 
14 
14 
14 
14 
14 
14 
14 
14 
14 
15 
15 
15 
15 
15 
15 
15 
15 
15 
15 
15 
15 
16 
16 
16 
16 
16 
16 
16 
16 
16 
16 
16 
16 


Mos. 
8 
9 
10 
11 
0 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
0 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
0 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 


Frequency 
0 
2 
3 

5  19 
1 
1 
2 
1 
2 
2 
2 
3 
0 
0 
1 
6 


21 


16 


10 


57 


Distribution  of  the  subjects  by  age. 

It  will  be  noted  that  only  19  of  the  116  subjects  are  under  eleven  years 
old. 


EVALUATED  AND  COMPARED 


11 


TABLE  II 
Grade  Distribution — 114  Cases. 


Grade 
I 

II 
III 
IV 
V 
VI 
VII 
VIII 

IX  or  I  H.  S. 

X  or  II  H.  S. 

XI  or  III  H.  S. 
XIIorlVH.S.  * 

Left  School 

VIII  1 

II  H.  S.  1 

The  vast  majority  of  subjects  were  in  the  Vlth  to  IXth  grades  in- 
clusive. 


2  had  left  school. 
Frequency 

1 

2 

2 
11 

7 
16 
10 
44 
12 

4 

5 

0 


INTELLIGENCE  QUOTIENT  DISTRIBUTION.      112   CASES. 

Scale: — 1  square  to  1  child 

70  means  70.000  to  79.999  etc. 
The  curve  of  distribution  is  skewed  positively. 


100 


uo 


130 


130 


140 


12 


SOME  WELL-KNOWN  MENTAL  TESTS 


TABLE  III 

DISTRIBUTION 

OF  INTRTJ.IGBNCE  QUOTIENTS — 112 

CASES. 

I.  Q. 

Frequency 

I.  Q. 

Frequency 

I.  Q. 

Frequency 

70 

0 

95 

2 

120 

0 

71 

0 

96 

3 

121 

1 

72 

0 

97 

4 

122 

2 

73 

1 

98 

2 

123 

0 

74 

1 

99 

3 

124 

0 

75 

0 

100 

7 

125 

1 

76 

1 

101 

7 

126 

2 

77 

0 

102 

4 

127 

2 

78 

0 

103 

2 

128 

1 

79 

0 

104 

0 

129 

0 

80 

1 

105 

5 

130 

3 

81 

0 

106 

4 

131 

1 

82 

0 

107 

3 

132 

1 

83 

0 

108 

2 

133 

0 

84 

1 

109 

2 

134 

1 

86 

2 

110 

1 

135 

0 

86 

2 

111 

1 

136 

1 

87 

1 

112 

1 

137 

0 

88 

2 

113 

3 

138 

0 

89 

3 

114 

2 

139 

0 

90 

1 

115 

1 

140 

0 

91 

2 

116 

4 

141 

1 

92 

1 

117 

1 

142 

0 

93 

4 

118 

2 

143 

0 

94 

4 

119 

2 

144 

0 

4  were  not  given  the  Stanford-Binet  test. 

Average  104.5 

Mental  age  in  months 

Average  154.8 

Mean  Square  Deviation  34.54 

The  table  shows  that  very  few  of  the  children  tested  had  I.  Q.'s  below 
normal. 

Age-Grade  Distribution 


CHRONOLOGICAL   AGE 


6.5 

7.5 

8.5 

9.5 

10.5 

11.5 

12.5 

13.5 

14.5 

15.5 

16.5 

Total 
cases 

I 

1 

1 

II 

2 

2 

III 

1 

1 

IV 

1 

6 

3 

2 

12 

V 

2 

3 

1 

1 

7 

VI 

6 

10 

16 

VII 

1 

5 

2 

2 

10 

VIII 

5 

9 

15 

11 

6 

46 

IX 

7 

3 

1 

11 

X 

1 

2 

2 

5 

XI 

1 

4 

5 

Total 

3 

2 

8 

6 

10 

21 

19 

22 

15 

10 

116 

EVALUATED  AND  COMPARED 


13 


CHRONOLOGICAL  AGE 


Chronological  age — mental  age  distribution. 

6.5     7.5    8.5     9.5    10.5    11.5    12.5    13.5    14.5    15.5    16.5  Total 


6.5 

cases 

7.5 

1 

1 

8.5 

2 

1 

1 

1 

5 

9.5 

3 

1 

1 

1 

6 

10.5 

1 

2 

3 

2 

2 

10 

11.5 

1 

1 

3 

1   6 

12.5 

1 

1 

3 

4 

2 

3 

1   15 

13.5 

4 

1 

4 

1 

10 

14.5 

2 

3 

2 

6 

6 

3  22 

15.5 

2 

4 

8 

14 

16.5 

3 

4 

2 

1 

1   11 

17.5 

2 

1 

1   4 

18.5 

3 

1 

1   5 

19.5 

1 

2   3 

Total 

3 

2 

7 

6 

10 

20 

17 

20 

16 

10  112 

Mental  age — grade  distribution. 

I       II      III     IV     V      VI    VII  VIII    IX     X    XI 


6.5 

7.5 

8.5 

9.5 

10.5 

11.5 

12.5 

13.5 

14.5 

15.5 

17.5 

16.5 

18.5 

19.5 

Total 


11 


7      17 


1 
6 
5 

15  2 

11  1 

1  1 

4  5 

1  2 

1 

44  12 


Total 
cases 

1 
6 

7 
10 

7 
14 
10 
22 
13 

4 
11 

4 

3 

3 


TESTS    BRIEFLY    DESCRIBED    AND    REASONS    FOR 
THEIR  SELECTION 

The  large  number  of  tests  available  had  to  be  classified  so 
as  to  find  which  tests  covered  identical  ground;  only  one  of 
these  was  then  selected.  Time  M^as  an  element  particularly  to  be 
recorded  since  preferably  less  than  three  hours  should  be  de- 
voted to  each  child  for  the  completion  of  all  tests.  This  allot- 
ment of  time  is  considered  by  most  authorities  to  be  generous, 
particularly  since  the  Stanford-Binet  takes  nearly  three  quar- 
ters of  an  hour,  thus  leaving  only  tv^o  hours  for  all  the  other 
tests.  Consequently  between  alternate  tests  apparently  serv- 
ing the  same  purpose  the  briefer  one  was  chosen.  The  same 
limitation  on  the  amount  of  time  to  be  spent  on  any  one  indi- 
vidual caused  the  necessary  omission  of  some  tests  which  were 
highly  desirable  except  as  to  their  length.  In  the  last  men- 
tioned class  are  group  tests  requiring  an  hour  or  more  to  be 
applied.  Where  the  results  that  are  sought  can  be  reached  by 
group  tests  doubtless  much  time  can  be  saved  in  using  them, 
but  the  inquiries  involved  herein  were  such  as  to  necessitate 
largely  individual  testing. 

In  selecting  the  tests  another  danger  that  was  realized  and 
that  it  was  attempted  to  avoid,  although,  as  the  results  show, 
not  with  entire  success,  was  that  a  great  many  tests  involved 
many  sides  of  mental  activity  so  that  the  final  result  expressed 
numerically  would  not  be  indicative  of  which  mental  abilities 
had  tested  favorably  and  which  unfavorably.  For  instance, 
ability  to  deal  with  abstract  and  with  concrete  material  may 
be  extreme  opposites  giving  a  correlation  of  minus  100.  If 
both  kinds  of  material  are  combined  in  one  test,  the  child  who 
succeeds  in  one  may  fail  in  the  other  and  vice  versa.  In  com- 
puting the  final  scores  compensation  will  give  the  same  net  re- 
sult to  two  children  of  exactly  opposite  capabilities.  If  gen- 
eral intelligence  is  what  we  want  we  may  find  it  in  this  way, 
but  if  we  are  interested  in  special  abilities  or  disabilities  these 
tests  which  hide  them  must  not  be  used.  We  have  found  this 
confusion  to  exist  in  many  tests,  of  course,  never  in  such  an 
extreme  form  as  in  the  illustration  above,  and  undoubtedly 
introduced  on  purpose,  but  we  feel  that  its  value  is  at  all  times 
questionable.     This  error  is  extremely  difficult  to  eliminate 

14 


EVALUATED  AND  COMPARED  15 

completely,  in  fact  we  can  not  be  sure  even  now,  as  it  will  ap- 
pear later  in  the  results,  that  we  have  successfully  done  so. 

Another  source  of  error  too  often  overlooked  was  borne  in 
mind  in  selection  of  the  tests,  namely  the  variability  of  the 
test  that  is  being  considered.  Where  the  same  test  is  applied 
to  a  person  at  intervals  and  it  is  found  that  the  resulting 
scores  are  not  identical  the  question  arises  whether  the  vary- 
ing scores  can  be  combined  so  as  to  give  a  reliable  standard  for 
use  and  comparison  with  the  results  obtained  when  the  test  is 
applied  to  other  children,  or  whether  the  variation  indicates  an 
unreliability  in  the  test  itself  sufficiently  serious  to  warrant 
the  test  being  discarded.  As  an  example  of  variations  of  such 
minor  character  that  their  existence  does  not  indicate  unre- 
liability, and  which  can  be  compeijsated,  we  can  take  the  tap- 
ping test  where  there  may  be  a  variation  of  about  five  taps  in 
each  direction  from  the  average,  which  would  be  entirely  sat- 
isfactory. Such  variations  are  due  to  unessential  and  insig- 
nificant details  of  the  conditions  under  which  the  test  is  re- 
peated, such  as  posture  of  the  child  being  tested,  kind  of  pen- 
cil or  stylus  being  used,  etc.  Taking  ten  or  more  measures  of 
tapping  ability  would  increase  the  reliability  but  the  final  re- 
sults would  show  such  slight  difference  from  the  result  of  one 
or  two  trials  that  the  frequent  repetition  is  entirely  uncalled 
for  to  secure  reasonable  reliability. 

On  the  other  hand,  if  the  variations  in  result  obtained  by  re- 
peated use  of  a  test  on  the  same  individual  are  not  of  a  minor 
character  and  if  the  day-to-day  variability  is  so  erratic  that 
the  variation  is  all  the  way  from  good  performance  to  poor 
performance,  then  the  situation  is  either  that  the  child  tested 
is  shown  to  be  subject  to  mental  disturbance,  or  that  the  test 
itself  shows  a  high  and  dangerous  variability.  If  it  is  the  test 
that  is  variable,  it  is  obviously  essential  to  weed  it  out  ab  initio. 
Such  variability  has  been  found  to  exist  in  the  Knox  cube  test, 
in  the  application  of  which  a  uniformly  normal  child  may 
make  the  record  of  an  imbecile  one  day  and  of  a  super-normal 
child  the  next  day.  Of  course,  such  a  test,  if  not  eliminated, 
would  lead  to  results  that  are  valueless  for  comparative  pur- 
poses and  dangerous  for  diagnostic  ones. 

As  to  variability,  the  reliability  of  a  number  of  tests  was  es- 
tablished and  recorded  before  the  study  was  undertaken.  As 
to  the  remaining  tests,  in  order  to  overcome  the  possible  exist- 
ence of  variations  indicating  unreliability  it  was  necessary  to 


16  SOME  WELL-KNOWN  MENTAL  TESTS 

retest  each  child  with  the  same  or  with  a  similar  test  after  an 
interval  of  a  week — no  less  or  practice  effect  would  be  met,  no 
more  to  avoid  the  effect  of  any  mental  growth  in  the  interval. 

The  necessity  of  retesting  caused  by  possible  variability  in 
the  test  itself,  led  to  the  subordinate  but  difficult  problem  of 
determining  what  methods  of  retesting  would  avoid  errors 
due  to  the  process  itself.  Thus,  as  has  been  mentioned,  retest- 
ing must  be  done  in  such  a  manner  as  to  avoid  practice  effect. 
It  has  been  shown  by  various  workers  that  certain  types  of 
tests  once  solved,  such  as  most  puzzles,  are  no  longer  tests  at 
all,  whereas  others,  such  as  auditory  memory  for  digits  and 
psychomotor  control,  show  a  minimum  effect,  which,  after  the 
week  between  tests,  is  negligible.  Those  of  our  tests  which 
come  within  the  last-mentioned  class  were  similarly  repeated. 
Those  which  were  of  the  former  type  had  similar  tests  substi- 
tuted for  them  in  the  second  trial,  while  still  others  falling  be- 
tween these  classes  were  altered  in  details  so  that  the  same 
test  could  be  repeated,  avoiding  the  memory  aspect. 

The  tests  finally  selected  were: 

1.  The  Stanford  revision  of  the  Binet-Simon  scale.  This 
test  is  so  widely  known  that  it  does  not  seem  to  be  necessary 
to  describe  it  here. 

2.  Pintner's  mental  survey  non-language  group  test,  with 
Myers  Mental  Measure  as  an  alternate  for  repeating.  These 
tests  involved  a  minimum  use  of  language.  In  the  Pintner 
test  no  language  is  used  in  the  performance,  and  in  fact  it  is 
possible  to  give  this  test  to  foreigners  or  deaf  children  through 
the  medium  of  signs,  while  in  giving  the  Myers  Mental  Meas- 
ure it  is  necessary  for  the  subject  to  understand  simple  lan- 
guage, but  none  is  used  in  executing  the  test.  The  Pintner  test 
has  six  parts,  the  first  resembling  the  Knox  cube  test,  the  sec- 
ond and  third  being  substitution  tests,  the  fourth  a  drawing 
completion,  while  the  fifth  is  a  reversed  drawing  test,  and  the 
sixth  a  picture  reconstruction.  Following  directions.  Pictori- 
al Completion,  and  two  tests  of  picking  out  objects  with  com- 
mon elements,  compose  the  Myers  test. 

3.  Thorndike's  reading  scale  Alpha  2.  This  is  a  test  in 
which  language  plays  a  prominent  part.  The  subject  reads 
a  paragraph  and  then  reads  certain  questions  based  upon  the 
paragraph  to  which  he  writes  his  answer.    To  succeed  he  must 

understand  the  context  of  the  paragraph,  he  must  understand 
the  question  and  know  what  it  calls  for,  and  he  must  be  able 


EVALUATED  AND  COMPARED  17 

to  find  the  answer  in  the  context  and  write  it  down.  This  is  a 
graded  test  which  is  applicable  from  the  second  grade  through 
high  school.  Since  the  practical  work  of  this  research  was 
undertaken,  Dr.  McCall  of  Teachers  College  has  considerably 
increased  the  usefulness  of  this  test  by  devising  ten  sets  iden- 
tical in  method  but  with  different  contents,  of  which  the  test 
here  used  is  one.  It  is  now  known  as  the  Thomdike-McCall 
reading  scale  and  its  reliability  has  been  thoroughly  estab- 
lished. 

4.  Healy's  Pictorial  Completion  Test  B  is  an  apperception 
test  with  the  language  element  omitted.  The  ten  pictures 
(plus  one  sample)  present  a  day's  activities  of  a  young  school 
boy,  in  which  each  picture  contains  a  situation  known  to  every 
child,  such  as  eating  breakfast,  the  school  cloak  room,  a  street 
accident,  etc.  In  each  picture  one  important  element  is  lack- 
ing; pieces  which  complete  the  picture,  plus  fifty  more  of  the 
same  size  being  arranged  in  a  definite  order  in  a  box  from 
which  the  subject  is  at  liberty  to  choose  those  which  he  desires. 
A  clue  to  the  missing  piece  is  furnished  by  the  pictures. 

5.  Porteus  Maze  Tests.  Vineland  Revision  1919.  These 
tests  are  supposed  to  measure  social  fitness  and  common  sense. 
Among  the  capacities  which  they  were  devised  to  measure  are 
forethought  and  planning  capacity,  prudence  and  mental 
alertness  in  meeting  a  situation  new  to  experience.  There  are 
eleven  mazes,  graded  in  difficulty  from  year  three  to  fourteen. 
Beginning  with  year  five,  avoidance  of  blind  alleys  is  the  main 
requirement  for  a  successful  performance.  The  more  complex 
the  maze,  the  further  ahead  must  one  look  in  order  to  be  cer- 
tain that  one  is  choosing  the  correct  path.  There  is  no  time 
limit;  in  fact  no  mention  of  speed  is  made,  and  if  the  child 
asks  he  is  told  to  do  it  as  well  as  possible,  taking  as  long  as  he 
likes.  Porteus  says  that  children  fail  mainly  because  of  im- 
pulsiveness in  action,  overconfidence  and  carelessness,  lack 
of  pre-consideration,  lack  of  planning  capacity,  irresolution 
and  mental  confusion,  inability  to  sustain  attention,  or  to 
profit  by  past  mistakes. 

6.  Tapping  Tests — Healy's  Form.  This  consists  of  a  sheet 
containing  one  hundred  and  fifty  half  inch  squares,  arranged 
ten  in  a  row — fifteen  rows.  The  subject  taps  once  in  each 
square,  vdthout  touching  the  lines  and  covers  as  much  ground 
as  he  can  in  thirty  seconds.  This  is  a  simple  test  of  psycho- 
motor control  which  was  repeated  without  alteration. 


18  SOME  WELL-KNOWN  MENTAL  TESTS 

This  test  in  a  slightly  different  form  was  first  introduced  by 
Cattell  in  1896,  for  testing  freshmen  at  college.  He  had  one 
hundred  1  cm.  squares,  into  each  of  which  the  student  must 
put  a  dot,  completing  the  task  as  quickly  as  possible.  Time 
was  recorded ;  evidently  there  were  no  errors.  This  test  was 
supposed  to  measure  rate  of  movement.  Clark  Wissler  used 
it  with  many  of  Cattell's  other  tests  in  his  "Correlation  of 
Mental  and  Physical  Tests"  on  college  freshmen  in  1901.  He 
found  that  the  average  time  for  men  was  34  seconds,  for  wom- 
en 30.8  seconds.  In  1911  Whitley:  (M.  T.  Whitley,  An  Em- 
pirical Study  of  Certain  Tests  for  Individual  Differences)  re- 
ports results  on  Cattell's  test,  in  which  she  kept  the  time 
constant  (30  seconds)  but  computed  the  length  of  time  which 
it  would  take  to  complete  the  blank.  We  have  found  the  ad- 
ditional fifty  squares  useful  in  that  some  of  our  cases  marked 
over  one  hundred  squares  in  the  thirty  second  time  limit. 

7.  Healy's  Construction  Tests  A.  and  B.  The  Knox-Moron 
test  and  Knox  Modification  of  Healy  A — a  diamond-shaped 
frame,  were  used  as  alternates.  We  have  called  these  A 
and  B  respectively  to  correspond  with  the  Healy  tests  and  for 
convenience.  The  equipment  for  these  tests  consists  of  a  board 
containing  one  or  more  openings  into  which  the  child  tested 
is  supposed  to  fit  pieces  of  wood  so  shaped  that  when  properly 
arranged  they  will  just  close  up  the  apertures.  An  advantage 
of  these  tests  is  the  convenient  size  of  the  materials  required. 
As  all  materials  had  to  be  carried  from  place  to  place  the  use 
of  clumsy  form  boards  or  the  tapping  board  with  its  dry  bat- 
teries, metal  plate  and  stylus,  was  practically  out  of  the  ques- 
tion. Where  other  things  were  equal,  tests  having  the  least 
paraphernalia  were  to  be  preferred. 

8.  The  Crossline  Tests  shown  in  the  figure  were  also  given. 

The  crossline  tests  were  included  because  they  are  a  modi- 
fication of  the  famous  Code  test,  which  is  generally  considered 
one  of  the  best  in  the  whole  Stanf  ord-Binet  series.  They  take 
very  little  time  to  give  and  can  easily  be  modified  for  repeti- 
tion. 

9.  Healy  and  Brenner  Learning  Tests. — These  tests  were  de- 
vised to  test  learning  ability,  not  as  in  the  skill  experiment,  but 
as  it  is  found  essential  in  the  elementary  school  subjects. 
Learning  test  A — the  association  of  two  symbols,  a  figure  and 
a  number,  resembles  other  substitution  tests  such  as  those  of 
Woodworth  and  Wells,  Pintner,  and  especially  Woolley.    The 


EVALUATED  AND  COMPARED 
I.    Crossline  Test 


19 


II.    Crossline  Test 


1 

4 

7 

2 

5 

8 

3 

6 

9 

I 

2 

3 

4 

5 

6 

7 

8 

9 

(c) 

(a)  and 


(d) 


(c)   are  the  forms  used  generally. 
(b)  and  (d)  were  used  for  retesting. 

difference  lies  in  the  fact  that  three  trials  were  given  and  speed 
of  learning  determined  success.  Learning  test  B  is  the  associa- 
tion of  a  symbol  with  a  sound,  as  in  learning  a  language.  The 
sjmibols  are  from  the  Phoenician  alphabet,  and  the  sounds  con- 
sist of  one  or  two  consonants  and  a  vowel,  simple  enough  to 
pronounce  but  without  meaning.  This  prevents  older  children 
from  forming  associations  which  would  be  impossible  for  those 
who  did  not  know  the  meaning  of  the  syllables.  Test  C  is  the 
association  of  a  symbol  and  a  value  presented  audibly,  and  test 
D  is  the  association  of  ideas  with  a  picture.  The  first  three 
test  a  sort  of  rote  ability  whereas  the  latter  tests  learning  of 
ideas. 

It  seems  reasonable  that  success  in  school  work  may  depend 
as  largely  upon  learning  ability  as  upon  mental  capacity,  es- 
pecially in  the  early  grades  where  the  chief  requirement  in 
most  of  our  schools  is  a  good  rote  memory,  as  in  learning  mul- 
tiplication tables,  and  these  two  do  not  necessarily  go  together. 
Certain  clinical  cases  bear  out  this  suggestion,  and  these  tests 


20  SOME  WELL-KNOWN  MENTAL  TESTS 

were  included  to  ascertain  the  reactions  of  normal  unselected 
children  in  this  respect. 

National  Intelligence  tests  were  not  yet  published  in  Novem- 
ber and  December,  1919,  when  this  study  was  begun,  or  they 
would  surely  have  been  considered  and  very  likely  used. 


METHOD— APPLYING  TESTS  TO  SUBJECTS 
General  Considerations 

All  of  the  tests  except  the  non-language  group  tests  and  the 
Thorndike  Alpha  2  were  given  to  the  subjects  individually. 
The  non-language  tests  were  given  sometimes  individually 
and  sometimes  in  groups  of  about  ten  with  one  exception 
where  thirty  eighth  grade  boys  were  tested  in  a  group. 

The  time  of  day  at  which  the  tests  were  given  varied  consid- 
erably. About  fifty  of  the  subjects,  from  the  Children's  Home 
and  from  the  Settlement,  were  tested  in  the  evening.  All 
others  were  tested  in  the  daytime. 

Care  .was  taken  to  avoid  giving  any  tests  while  the  subject 
might  be  fatigued.  Each  child  was  questioned  regarding  the 
matter  and  whenever  there  were  indications  of  fatigue  the 
testing  was  always  postponed. 

Usually  a  subject  was  tested  for  only  an  hour  and  a  half  at 
one  time;  frequently  the  duration  of  the  testing  was  shorter 
and  only  occasionally  was  it  longer. 

The  tests  were  all  scored  according  to  the  directions  laid 
down  by  their  respective  authors.  They  were  all  scored  per- 
sonally by  the  examiner  twice.  In  all  of  the  tests  selected  for 
use  the  scoring  is  objective  and  requires  no  technique.  Where 
possible,  score  cards  or  keys  were  used.  Where  the  time  taken 
by  a  subject  to  complete  a  test  was  to  be  recorded,  the  timing 
was  done  by  means  of  a  stop  watch. 

Much  effort  was  expended  in  persuading  the  subjects  to  give 
an  equal  amount  of  attention  and  concentration  to  all  of  the 
tests,  so  that  the  results  would  not  be  affected  by  individual 
preferences.  For  a  large  proportion  of  the  subjects  the  incen- 
tive of  vocational  guidance  was  offered  and  some  general  voca- 
tional advice,  based  partly  on  the  experience  of  the  examiner 
as  well  as  on  the  tests,  was  given  at  the  conclusion  of  the  test- 
ing. Younger  children  needed  no  incentive  and  their  enthusi- 
asm was  so  pronounced  that  they  continually  applied  to  take 
more  than  the  regular  number  of  tests. 

Supplementary  information  concerning  the  subjects  was 
gathered  and  recorded,  especially  age  in  months,  school  grade, 
success  in  school  work,  marks,  standing  in  class,  whether  a 

21 


22  SOME  WELL-KNOWN  MENTAL  TESTS 

repeater  and  how  often,  whether  subject  skipped  any  grades, 
etc.  The  vocational  plans  and  interests  of  the  older  children 
were  obtained  whenever  they  had  any.  Results  of  physical  ex- 
amination were  obtainable  for  a  large  per  cent  of  the  cases. 
Several  subjects  had  also  been  given  neurological  examina- 
tions. Occasionally  some  result  can  be  explained  by  reference 
to  these  findings,  as  for  instance  an  unaccountably  poor  per- 
formance on  the  Healy  Pictorial  Completion  test  which  was 
probably  due  to  uncorrected  vision.  One  case  where  peculiar 
results  were  obtained  from  the  tests  was  explained  by  the 
physical  examination  which  showed  a  history  of  epilepsy 
and  thereupon  the  case  was  no  longer  considered. 

Specific  Observations  on  the  Application  of  the 
Tests  Selected 

Stanford-Binet. — In  the  United  States  there  have  been  sev- 
eral revisions  of  the  Binet-Simon  test,  the  most  recent  and  well 
the  best  of  these  being  that  by  Professor  Lewis  M.  Terman  of 
Leland  Stanford  University,  California,  published  in  its  final 
form  in  1916.  This  revision,  called  the  Stanford-Binet,  was 
the  one  used  in  this  study.  The  score  obtained  in  the  Stanford- 
Binet  test  is  expressed  in  years  and  months,  mental  age.  This 
mental  age,  when  divided  by  the  life  age,  results  in  the  intel- 
ligence quotient,  which  is  expressed  as  a  decimal.  There  have 
been  some  wrongful  uses  of  the  intelligence  quotient.  It  is  an 
attractive  but  erroneous  idea  that  a  certain  intelligence  quo- 
tient can  be  found  below  which  all  can  be  considered  feeble 
minded  while  all  above  are  normal  or  supernormal.  The  error 
in  this  idea  has  been  pointed  out  by  Fernald,  Mateer,  Kohs, 
and  others,  who  demonstrate  the  degree  of  overlapping,  and 
show  how  valueless  the  I.  Q.  is  when  reported  without  refer- 
ence to  life  age. 

The  Stanford-Binet  results  can  be  analyzed,  as  well  as 
summed  up  in  the  I.  Q.,  and  it  is  possible  that  a  detailed  analy- 
sis of  the  data  would  yield  all  the  information  required.  The 
plea  that  general  intelligence  scales  have  a  right  to  be  so  called 
is  largely  based  upon  the  supposition  that  the  functions  which 
are  tested  are  manifold.  Auditory  memory  for  rote  material 
and  for  ideas,  visual  memory,  language  ability,  reasoning  abil- 
ity, apperceptions,  general  information  and  many  other  abili- 
ties— all  are  found  within  the  total  range  of  tests.     Unfor- 


EVALUATED  AND  COMPARED  23 

tunately,  in  the  Stanford  scale  no  child  gets  tested  in  all  these 
fields,  and  further,  since  they  are  not  standardized  separately 
the  significance  of  success  or  failure  in  one  part  is  difficult  to 
determine. 

The  Stanford-Binet  tests  were  all  given  by  the  writer  in 
the  manner  described  by  Terman.  It  is  unnecessary  to  repeat 
this  test  in  order  to  establish  its  reliability  as  the  reliability 
has  been  independently  reported  upon  by  Terman. 

The  vocabulary  and  memory  span  for  digits  of  the  Stanford- 
Binet  were  given  with  the  Porteus  tests,  the  remainder  of  the 
Stanford-Binet  taking  only  one  session. 

The  Alpha  2  Reading  Scale  was  scored  by  the  method 
worked  out  by  Kelley  and  his  tables  were  used. 

The  tapping  test  was  scored  for  number  of  taps  and  errors. 

In  the  construction  tests  number  of  moves  and  time  were 
taken  and  when  the  test  was  not  completed  within  the  limit  of 
five  minutes  it  was  scored  as  a  failure  and  the  number  of 
moves  up  to  that  time  was  noted. 

A  construction  test — once  solved — is  much  easier  to  solve 
a  second  time  unless  the  first  solution  was  due  to  chance. 
Healy  A  was  repeated  in  order  to  check  the  first  performance. 
In  Healy's  construction  test  B  a  second  trial  generally  brings 
a  result  as  near  perfect  as  possible  (that  is,  dependent  only  on 
skill  and  speed  in  motor  performances),  even  if  the  first  solu- 
tion was  hit  upon  by  chance.  It  is  impossible  to  do  away  with 
the  chance  element  in  performance  tests,  but  in  order  to  guard 
against  it  as  much  as  possible,  two  tests  were  used  each  time, 
and  the  selection  was  made  after  a  study  of  many  types. 
There  are  several  difficulties  in  making  this  choice  and  we 
were  impressed  by  the  fact  that  most  performance  tests  have 
not  been  standardized  and  that  there  are  very  few  tests  of  this 
kind  which  are  sufficiently  difficult  for  older  subjects.  The 
Healy  and  Knox  tests  satisfied  both  of  these  conditions. 

The  scoring  for  the  learning  tests  is  rather  complicated. 
A  perfect  score  on  all  four  tests  is  four  hundred,  one  hundred 
being  the  perfect  score  for  each  test.  Learning  test  A  has 
twelve  elements,  and  if  these  were  all  correct  on  the  three 
trials,  thirty-six  elements  would  receive  a  mark  of  one  hun- 
dred, or  each  would  get  2.8.  Thus  the  score  equals  the  number 
correct  multiplied  by  2.8.  When  a  perfect  score  is  made  on  the 
first  or  second  trial,  it  is  assumed  that  further  trials  would 
give  a  perfect  score  also.     In  learning  test  B  there  are  five 


24  SOME  WELL-KNOWN  MENTAL  TESTS 

symbols  in  each  of  the  three  trials, — consequently  each  re- 
ceives a  value  of  6.7.  In  test  C  there  are  seven  symbols  and 
three  trials.  Dividing  one  hundred  by  three  times  seven 
there  results  a  value  of  4.7  for  each,  vi^hile  in  test  D,  which  has 
ten  items,  the  total  number  is  thirty,  with  a  value  of  3.3  each. 
The  total  for  all  the  tests  is  the  sum  of  the  score  on  each  of  the 
four. 


RESULTS 

Where  a  clinician  is  generally  satisfied  to  take  the  score  ob- 
tained by  applying-  a  test  as  a  final  goal,  if  in  fact  he  goes  so 
far  as  to  work  out  a  score,  it  is  obvious  that  to  attain  the  pur- 
poses here  in  mind  the  scores  of  the  various  tests  used  must  be 
compared  to  gather  statistics  reflecting  their  qualities.  That 
is,  M^hen  the  one  hundred  and  sixteen  children  had  been  given 
the  tests  that  were  selected  and  when  the  scores  were  recorded, 
the  field  work  was  completed,  but  there  remained  to  investi- 
gate in  a  laboratory  manner  what  a  combination  of  the  re- 
sults would  show  with  reference  to  the  purposes  of  this  study. 

This  comparison  of  results  was  made  by  correlation,  that  is, 
by  measuring  the  mutual  implications  (see  Thorndike,  Mental 
and  Social  Measurements,  pp.  156-185).  A  test  is  to  be  evalu- 
ated in  three  ways;  its  correlation  with  criteria  other  than 
results  of  tests;  its  self -correlation,  and  its  correlation  with 
other  tests.  In  the  present  inquiry  we  obtained  no  outside 
criteria  with  which  to  correlate  our  tests,  because  no  outside 
criteria  available  could  be  relied  upon.  In  the  field  of  mental 
abilities,  the  only  criteria  which  have  been  widely  used  are 
teachers'  opinions,  school  marks,  etc.  These  are  unsatisfac- 
tory at  best.  Although  we  possess  all  these  data  for  our  cases 
we  consider  them  useless  since  the  children  attended  eight  dif- 
ferent schools  in  four  places,  with  the  marking  systems  vary- 
ing for  each.  We  compared  judgments  as  to  intelligence  made 
by  the  teacher  of  the  ninth  grade  of  the  Woodmere  school  with 
those  made  by  the  eighth  grade  teacher  of  the  New  York  Pub- 
lic School.  In  the  former  the  I.  Q.'s  varied  from  95  to  141 ;  in 
the  latter  from  73  to  116.  In  the  former  all  but  two  children 
tested  as  supernormal  and  the  class  average  was  121,  where- 
as in  the  latter  only  one  tested  above  110  with  a  class  average 
of  96.  But  to  read  the  teachers'  judgments  one  would  think 
that  the  pupils  of  the  latter  school  were  considerably  more  in- 
telligent than  those  of  the  former.  Even  the  comparative  rat- 
ings within  one  group  were  markedly  unreliable.  They  showed 
all  the  errors  of  judgment  pointed  out  by  Terman.  No  account 
was  taken  of  age;  the  best  behaved,  most  conscientious  pupil 
was  invariably  considered  the  most  intelligent,  etc.  What  is 
the  use  of  making  correlations  with  this  kind  of  material, 

25 


26  SOME  WELL-KNOWN  MENTAL  TESTS 

when  one  knows  in  advance  that  all  the  fault  of  a  low  correla- 
tion will  be  attributed  to  the  criterion,  and  the  tests  will  stand 
as  before — unknown  quantities!  Moreover,  these  criteria 
could  only  be  used  to  represent  a  measure  of  general  intelli- 
gence. The  teachers  admittedly  knew  practically  nothing 
about  the  special  abilities  of  their  pupils ;  the  parents,  where 
consulted,  knew  very  little  more.  A  rating  on  general  intelli- 
gence has  been  frequently  correlated  with  general  intelligence 
tests,  and  the  results  published.  Our  data  would  present  no 
new  factors. 

Consequently  we  have  not  evaluated  the  tests  by  means  of 
correlation  with  outside  criteria  but  we  do  have  the  data  for 
self-correlations  and  for  inter-correlations.  Where  various 
tests  which  we  used  intercorrelate  extremely  highly,  we  may 
feel  that  they  are  measuring  the  same  thing.  On  the  other 
hand,  if  the  intercorrelations  approach  zero  or  are  negative, 
the  results  indicate  that  we  have  no  evidence  that  aspects  of 
intelligence  are  being  measured  at  all.  Only  if  the  correla- 
tions are  sufficiently  high  to  indicate  that  intelligence  is  being 
measured  and  low  enough  to  show  that  different  factors  are 
entering  into  the  different  tests,  can  we  consider  the  tests 
worthy  of  being  included  in  mental  examination.  In  judging 
our  correlations  we  must  remember  that  we  are  testing  nor- 
mal children  only, — ^therefore  our  coefficients  are  lowered — 
and  that  our  ages  do  not  cover  a  large  area,  which  also  lowers 
the  coefficients  of  correlation. 

Our  conclusions  are  limited  to  the  tests  we  used  but  the  gen- 
eral method  of  dealing  with  the  scores  has  a  wide  applicability. 

Table  IV 

DISTRIBUTION   OF  PINTNER  SCORES — 100  CASES 


Score 

Frequency 

Score 

Frequency 

200-209.9 

0 

370-379.9 

3 

210-219.9 

0 

380-389.9 

5 

220-229.9 

1 

390-399.9 

2 

230-239.9 

0 

400-409.9 

4 

240-249.9 

0 

410-419.9 

5 

250-259.9 

1 

420-429.9 

5 

260-269.9 

0 

430-439.9 

7 

270-279.9 

1 

440-449.9 

4 

280-289,9 

1 

450-459.9 

5 

290-299.9 

2 

460-469.9 

7 

300-309.9 

1 

470-479.9 

5 

310-319.9 

1 

480-489.9 

1 

320-329.9 

2 

490-499.9 

4 

330-339.9 

4 

500-509.9 

6 

340-349.9 

2 

510-519.9 

4 

EVALUATED  AND  COMPARED 


27 


Score 
350-359.9 
360-369.9 


TABLE  IV- 
Frequency 
6 
8 


-Continued 
Score 
520-529.9 
530-539.9 


16  were  not  given  the  Pintner  Test. 

The  evenness  of  distribution  of  scores  is  noticeable. 
Average=420.964.  Unreliability  6.9. 

Mean  Square  Deviation=r68.96.     Unreliability  4.9. 

Table  V 

DISTRIBUTION  OF  MYERS  SCORES — 90  CASES 


Frequency 
1 
2 


Score 

Frequency 

Score 

Frequency 

Score 

Frequency 

16 

0 

46 

0 

76 

1 

17 

1 

47 

1 

77 

1 

18 

0 

48 

3 

78 

0 

19 

0 

49 

1 

79 

0 

20 

1 

50 

2 

80 

0 

21 

0 

51 

1 

81 

2 

22 

1 

52 

4 

82 

1 

23 

1 

53 

4 

83 

0 

24 

0 

54 

2 

84 

1 

25 

1 

55 

2 

85 

0 

26 

1 

56 

0 

86 

0 

27 

1 

57 

3 

87 

2 

28 

2 

58 

2 

88 

0 

29 

2 

59 

2 

89 

0 

30 

0 

60 

2 

90 

0 

31 

1 

61 

1 

91 

1 

32 

0 

62 

3 

92 

0 

33 

2 

63 

3 

93 

0 

34 

2 

64 

3 

94 

1 

35 

0 

65 

2 

95 

0 

36 

3 

66 

0 

96 

0 

37 

1 

67 

0 

97 

0 

38 

1 

68 

2 

98 

0 

39 

0 

69 

3 

99 

0 

40 

1 

70 

1 

100 

0 

41 

1 

71 

1 

101 

0 

42 

0 

72 

1 

102 

0 

43 

4 

73 

1 

103 

1 

44 

0 

74 

0 

104 

0 

45 

2 

75 

0 

105 

0 

26  were 

not  given  test 

Average=53,325 

Unreliability  1.8. 

Mean  Square  Deviation^ 

il7.88. 

Unreliability 

1.3. 

Table  VI 

DISTRIBUTION  OF  ALPHA  SCORES — 107  CASES 


Score 

Frequency 

Score 

Frequency 

Score 

Frequency 

3.6 

2 

5.4 

1 

7.3 

7 

3.7 

0 

5.5 

1 

7.4 

6 

3.8 

0 

5.6 

1 

7.5 

12 

3.9 

0 

5.7 

1 

7.6 

2 

4.0 

0 

5.8 

0 

7.7 

6 

4.1 

3 

5.9 

2 

7.8 

1 

4.2 

1 

6.0 

0 

7.9 

2 

4.3 

0 

6.15 

1 

8.0 

2 

28 


SOME  WELL-KNOWN  MENTAL  TESTS 


Table  VI — Continued 


Score 

Frequency 

Score 

Frequency 

Score 

Frequency 

4.4 

0 

6.2 

3 

8.1 

1 

4.66 

1 

6.3 

0 

8.2 

2 

4.6 

0 

6.4 

2 

8.3 

2 

4.7 

3 

6.5 

1 

8.4 

1 

4.8 

1 

6.6 

3 

8.5 

2 

4.9 

2 

6.7 

6 

8.6 

0 

6.0 

1 

6.8 

4 

8.7 

0 

5.1 

3 

6.9 

3 

8.8 

1 

5.2 

6 

7.0 

1 

8.9 

0 

5.3 

0 

7.1 
7.2 

0 

7 

9.0 

1 

9  were  not  given  The  Alpha  Test. 

Average=6.834. 

Unreliability 

.116. 

Mean  Square  Deviation: 

=1.20.     Unreliability 

.082. 

TABLE 

VII 

DISTRIBUTION    OF    PICTORIAL    COMPLETION    TEST 

SCORES — 110 

CASES 

Score          Frequency 

Score           Frequency 

Score         Frequency 

^15  to    0 

2 

30  to  34.99 

6 

65  to  69.99 

12 

Oto  +5 

2 

35  to  39.99 

6 

70  to  74.99 

7 

5  to    9.99 

2 

40  to  44.99 

6 

75  to  79.99 

4 

10  to  14.99 

1 

45  to  49.99 

10 

80  to  84.99 

9 

15  to  19.99 

4 

50  to  54.99 

8 

85  to  89.99 

4 

20  to  24.99 

4 

55  to  59.99 

12 

90  to  94.99 

2 

25  to  29.99 

0 

60  to  64.99 

8 

95  to  99.99 

1 

6  were  not  given  test. 
Average=54.527. 
Mean  Square  Deviation=22.69. 


Unreliability  2.16 
Unreliability  1.5. 


Score 

170-179.9 

180-189.9 

190-199.9 

200-209.9 

210-219.9 

220-229.9 

230-239.9 

240-249.9 


LEARNING 

Frequency 
2 
0 
1 
0 
2 
1 
4 
1 


TABLE  VIII 

TESTS    DISTRIBUTION — 106    CASES 


Score 

250-259.9 

260-269.9 

270-279.9 

280-289.9 

290-299.9 

300-309.9 

310-319.9 

320-329.9 


Frequency    Score    Frequency 


4 
7 
6 
5 
8 
10 


330-339.9 
340-349.9 
350-359.9 
360-369.9 
370-379.9 
380-389.9 
390-399.9 
400-409.9 


10  were  not  given  the 
Average=300.66. 
Mean  Square  Deviation= 


tests;  3  none  at  all;  7  not  all  four. 

Unreliability=5.08. 
:52.31.  Unreliability=3.6. 

TABLE   IX 


PORTEUS 

SCORES 

DISTRIBUTION — 

•113    CASES 

Score 

Frequency 

Score 

Frequency 

Score 

Frequency 

5 

2 

8.5 

4 

11.5 

14 

5.6 

1 

9 

2 

12 

7 

6 

0 

9.5 

6 

12.5 

15 

6.5 

1 

10 

6 

13 

15 

7 

3 

10.5 

8 

13.5 

4 

7.5 

4 

11 

11 

14 

7 

8 

3 

3  were  not  ] 

give  this  test. 

Avera; 

ge=11.09. 

Unreliability 

.19. 

Mean 

Square 

Deviatioi] 

1=2.02. 

Unreliability 

.13. 

EVALUATED  AND  COMPARED  29 

TABLE   X 

DISTRIBUTION  OP  CROSSLINE  TEST  SCORES — 114   CASES 

Score         Frequency        Score  Frequency        Score        Frequency 

I       II  I       II  I       II 

Both  OK'  70  OK'-OK'  1  OK*-F  3 

OK'-OK'  13  OK'-OK'  2  OK'-F  1 

OK'-OK>  5  OK'-OK"  1  OK'-F  2 

OK'-OK*  5  OK*-OK*  2  OK*-F  1 

OK'-OK'  2  OK=-OK*  1  F    -F  5 

OK'=Correct  on  first  trial. 

OK'=Correct  on  second  trial. 

F=Failure  on  fourth  trial. 

TABLE  XI 

DISTRIBUTION  OF  TAPPING  SCORES.    AVERAGE  OP  2  TRIALS — 113  CASES 

Score         Frequency  Score          Frequency        Score        Frequency 

40  to  44.99          1  65  to  69.99           11  90  to    94.99  5 

45  to  49.99          3  70  to  74.99           13  95  to    99.^9  5 

50  to  54.99          5  75  to  79.99           23  100  to  104.99  2 

55  to  59.99          9  80  to  84.99           20  105  to  109.99  0 

60  to  64.99          9  85  to  89.99             6  110  to  114.99  1 

Average=73.43.  Unreliability  1.26. 

Mean  Square  Deviation=13.39     Unreliability  .89. 

TABLE  XII 

DISTRIBUTION    OP    CONSTRUCTION    AND    KNOX — TIME    108    CASES 

Score         Frequency      Score        Frequency  Score        Frequency 


50  to  99.99 

1 

350  to  399.99 

12 

650  to  699.99 

6 

100  to  149.99 

7 

400  to  449.99 

8 

700  to  749.99 

4 

150  to  199.99 

5 

450  to  499.99 

8 

750  to  799.99 

2 

200  to  249.99 

10 

500  to  549.99 

9 

800  to  849.99 

3 

250  to  299.99 

10 

550  to  599.99 

5 

850  to  899.99 

2 

300  to  349.99 

8 

600  to  649.99 

7 

900  to  949.99 
950  to  999.99 

0 
1 

Averagez=420  to  480  or  7.685. 
Mean  Square  Deviation=3.39. 

Tables  4  to  12  inclusive  show  the  distribution  of  scores  on 
the  various  tests.  The  average,  or  more  properly  speaking 
the  arithmetic  mean  and  mean  square  deviation,  are  also  given 
for  each. 

That  we  have  sufficient  cases  is  shown  by  the  relation  of  the 
variability  to  the  average.  In  only  a  few  instances  is  it  large 
enough  to  raise  a  doubt  as  to  whether  enough  cases  were  used. 
These  are  the  Pictorial  Completion  test,  the  Construction  tests, 
and  the  Myers  Mental  Measure.    The  formula  for  the  unreli- 

adis. 

ability  of  an  average  is  aT-obt.av.=: for  the  unreliability 

vn 

adis. 
of  a  mean  square  deviation  it  is  o-T-obtcrrr: These  data 

\/2ir 
are  also  included  in  the  tables.     (See  Thorndike,  Mental  and 
Social  Measurements). 


30  SOME  WELL-KNOWN  MENTAL  TESTS 

A  few  special  considerations  arose  at  once  with  reference  to 
the  crossline  tests,  the  tapping  test  and  the  construction  tests. 

The  crossline  test  has  no  value  for  our  subjects  (see  table 
X.) ;  one  hundred  and  fourteen  cases  were  tested,  out  of 
which  70,  or  over  60  per  cent,  made  perfect  scores ;  the  remain- 
ing 40  per  cent  ranging  almost  indifferently  from  one  error  to 
complete  failure.  This  test  is,  then,  far  too  easy  for  our  sub- 
jects, and  the  results  are  useless  for  our  purposes.  We  will 
disregard  it  completely  from  now  on. 

In  dealing  with  the  tapping  test  we  were  confronted  with 
the  problem  of  how  to  handle  the  errors.  Since  a  perfect  cor- 
relation would  be  expected  between  two  absolutely  perfect  tests 
of  tapping  ability,  the  highest  correlation  obtainable  is  pre- 
sumably the  one  which  best  accounts  for  the  errors.  On  this 
assumption  the  two  trials  of  fifty  cases  of  the  tapping  test 
were  correlated  both  by  Pearson  and  Spearman  formulae,  first 
disregarding  the  errors,  then  weighting  them  one  each,  and 
finally  weighting  them  two  points  each,  with  the  following 
results : 

Pearson  Spearman 

Erors   disregarded    r  =  .794     r  =    .917 

Errors  weighted  one  each r  =  .773    r  =    .90 

Errors  weighted  two  each r  =  .764    r  =    .82 

It  would  seem  then  that  the  errors  are  of  comparatively 
little  importance,  but  as  disregarding  them  gives  the  highest 
self-correlation,  they  will  be  omitted  in  any  correlations  in 
which  the  tapping  test  is  involved. 

A  similar  problem  is  presented  by  the  construction  tests, 
where  we  have  scores  for  time  and  moves:  Should  they  be 
combined  and  if  so,  how?  If  not,  are  they  both  important, 
or  only  one,  and  if  the  latter,  which  one?  In  order  to  arrive 
at  an  unbiased  conclusion — for  it  was  the  writer's  opinion 
that  time  was  by  far  the  most  valuable  measure — the  advice 
of  fifteen  other  persons  was  sought.  These  others  were  all 
familiar  with  the  tests,  and  had  used  them  extensively  in 
clinical  work.  By  far  the  majority  were  in  favor  of  using 
both  time  and  moves,  each  independently  of  the  other.  Two 
of  these  considered  the  moves  decidedly  more  important  than 
time ;  two  others  stated  that  time  alone  was  sufficient,  because 
time  and  moves  had  been  found  to  correlate  so  highly,  that 
the  difference  between  using  them  and  not  doing  so  was  within 


EVALUATED  AND  COMPARED  31 

the  probable  error  of  either  one.     None  recommended  at- 
tempting to  combine  them. 

The  following  correlations  were  therefore  made : 
Construction  A  with  B-time. 
Construction  A  withB-moves. 
Knox  A  with  B-time. 
Knox  A  with  B-moves. 
Average  Construction  A  and  B  with  average  Knox  A  and  B- 

time. 
Average  Construction  A  and  B  with  average  Knox  A  and  B- 

moves. 

If  the  test  was  not  completed  in  five  minutes  it  was  scored 
as  a  failure  and  the  number  of  moves  up  to  that  time  re- 
corded. Some  children  who  solve  the  test  in  three  minutes 
make  more  moves  than  others  who  fail  in  five  minutes.  How 
can  one  tell  how  many  moves  the  latter  would  have  made, 
had  they  completed  the  test?  Obviously,  the  number  they 
made  until  they  were  arbitrarily  stopped  is  not  a  fair  measure. 
It  was  finally  decided  to  omit  all  cases  where  any  construction 
test  was  a  failure,  from  the  moves  correlations. 

The  crude  scores  were  not  used  in  the  time  correlations, 
but  the  three  hundred  seconds  were  divided  into  twenty  groups 
of  fifteen  seconds  each.  Anyone  succeeding  with  a  test  in 
fifteen  seconds  or  less,  was  put  in  group  one;  if  he  took  more 
than  fifteen  seconds  and  less  than  thirty-one  seconds  he  was 
put  in  group  two,  and  so  forth.  All  who  failed  the  test  were 
put  in  group  twenty,  thus  making  it  possible  to  include  in 
these  correlations  many  cases  which  had  to  be  excluded  from 
the  correlations  of  number  of  moves  made. 

Taking  up  first  the  self-correlations,  that  is,  the  correla- 
tions of  our  alternate  tests,  with  each  other  or  the  correlations 
of  the  scores  obtained  by  repeated  use  of  the  same  test,  the 
results  were  as  follows: 

As  only  a  few  Stanford-Binet's  were  repeated,  the  results 
are  of  little  significance.  We  obtain  a  correlation  of  .89  on 
our  fourteen  cases.  L.  M.  Terman  ("The  Intelligence 
of  School  Children"  ch.  IX.)  had  retests  given  to  three  hun- 
dred and  fifteen  children,  out  of  which  forty-six  were  given 
three  or  more  tests.  The  interval  between  the  first  and  sec- 
ond testing  ranged  from  one  day  to  seven  years.  The  central 
tendency  of  change  is  represented  by  an  increase  of  1.7  in 


32  SOME  WELL-KNOWN  MENTAL  TESTS 

I.Q. ;  the  middle  fifty  per  cent  of  change  lies  between  the  limits 
of  3.3  decrease  and  5.7  increase.  Consequently  the  probable 
error  of  a  prediction  based  on  the  first  test  is  4.5  points  in 
terms  of  I.Q.  The  correlation  between  all  the  testings  is  .933. 
Apparently  whether  the  interval  be  a  few  months  or  several 
years  does  not  influence  the  result.  If  the  re-examination  be 
within  a  few  days,  the  I.  Q.  will — on  the  average — be  raised 
only  two  or  three  points,  and  this  when  no  restriction  has 
been  put  on  the  children  communicating  with  one  another. 
There  are  several  exceptions  to  this  general  rule,  one  being 
that  young  feeble-minded  children  tend  to  show  their  feeble- 
mindedness more  as  they  grow  older ;  that  is,  they  test  lower 
on  the  Stanford-Binet.  We  need  not  concern  ourselves  with 
this,  as  only  normal  children  were  included  in  this  study. 
Another  obvious  factor  which  tends  to  make  the  I.  Q.  appear 
unstable,  is  due  to  the  fact  that  the  test  is  limited  at  the  upper 
end.  As  a  child  with  a  high  I.  Q.  grows  older,  the  I.  Q.  drops 
until  at  the  age  of  sixteen  years  the  highest  I.  Q.  obtainable 
is  122.  In  many  pathological  cases  such  as  children  suffering 
from  epilepsy,  chorea,  etc.,  the  I.  Q.  fluctuates  considerably. 
But  even  within  the  ranges  of  normality,  Terman  thinks  that 
fluctuations  occur  for  at  least  three  reasons. 

1.  There  may  be  a  certain  amount  of  irregularity  in  the 
actual  rate  of  mental  development. 

2.  The  results  of  a  test  may  be  influenced  to  some  extent 
by  the  conditions  under  which  it  is  given,  the  state  of  the 
child's  health,  his  attitude  toward  the  test,  fatigue  and  other 
temporary  and  accidental  features. 

Retests  after  a  brief  interval  indicate  that  errors  from 
this  source  are  ordinarily  not  large. 

3.  There  is  inevitably  a  certain  amount  of  error  in  every 
I.  Q.  rating  due  to  imperfections  in  the  scale  used. 

What  has  been  generally  criticized  in  the  Stanford-Binet 
scale,  namely  that  it  measures  different  things  at  different 
years  and  consequently  that  a  subject  might  do  very  well 
when  his  memory  ability  for  example  was  tested,  and  very 
poorly  when  his  reasoning  ability  came  into  the  foreground 
a  couple  of  years  later,  does  not  seem  to  be  valid  on  actual 
findings.  The  theoretical  argument  against  such  a  criticism 
is  that  so  many  age  levels  are  tested  each  time  that  a  subject 
will  win  and  lose  points  in  every  branch  which  the  test  in- 
cludes. 


EVALUATED  AND  COMPARED  33 

The  Pintner  and  Myers  tests  were  chosen  to  measure  the 
same  thing,  and  so  we  expected  to  find  a  high  correlation  be- 
tween them.  The  Pearson  coefficient  of  .584  was  so  unex- 
pected that  we  felt  that  further  investigation  was  needed. 
A  closer  study  of  the  tests  revealed  the  fact  that  their  likeness 
rested  on  negative  similarity;  neither  involved  the  use  of 
language,  but  in  other  respects  they  apparently  required  dif- 
ferent abilities.  The  Pintner  test  appeared  more  limited,  more 
mathematical,  involving  concrete  situations  rather  than  gen- 
eralizations while  the  Myers  on  the  other  hand  was  more 
general,  but  rather  sketchy.  In  order  to  test  the  truth  of 
this  hypothesis,  the  six  Pintner  tests  were  intercorrelated  and 
also  the  four  Myers  tests — see  table.  The  average  of  the 
Pintner  intercorrelations  was  .234,  of  the  four  Myers  tests 
correlated  each  with  all  the  others,  .445.  It  will  therefore  be 
seen  that  the  above  explanation  is  unsatisfactory. 

TABLE  XIII 

PINTNER  TESTS  INTERCORRELATED 


1 

2 

3 

4 

5 

G   Composite 

1 

-.009 

.392 

.325 

.183 

.337 

.618 

2 

-.009 

.470 

.022 

-.022 

.107 

.396 

3 

.392 

.470 

.361 

.224 

.316 

.757 

4 

.325 

.022 

.361 

.035 

.456 

.625 

5 

.183 

-.022 

.224 

.035 

.307 

.540 

6 

.337 

.107 

.316 

.456 

.307 

.670 

Average 

.249 

.126 

.353 

.240 

.154 

.305 

Composite 

.618 

.396 

.757 

.625 

.540 

.670 

Average  of  all  above  correlations,  regarding  signs  +  .234. 
Average  of  all  above  correlations,  without  regarding  signs  +  .238. 
Probable  Error  of  each  correlation,  approximately  .05. 
Number  of  cases  100. 

The  fact  that  correlations  between  the  separate  Tests  are  low,  while 
those  of  each  Test  with  the  composite  of  all  6,  are  high,  indicates  merit 
in  the  Test  as  a  whole. 

TABLE  XIV 

MYERS    MENTAL    MEASURE    INTERCORRELATIONS 

12  3  4    Composite        Average  of  all 

above  correlations — 
+  .445 
1  .470        .469         .564        .786  Number  of  cases— 89 


2 

.470 

.346 

.424 

.796 

3 

.469 

.346 

.403 

.477 

4 

.564 

.424 

.403 

.775 

Composite 

.786 

.796 

.477 

.775 

The  comment  made  concerning  the  previous  Table — Pintner  Tests — 
applies  to  some  extent  to  the  Myers  Test  also.  However,  the  correla- 
tions between  the  separate  tests  are  much  higher  than  those  found  be- 
tween the  Pintner  Tests. 


34  SOME  WELL-KNOWN  MENTAL  TESTS 

For  if  the  Pintner  tests  were  all  of  the  same  nature,  includ- 
ing the  same  factors,  their  intercorrelations  would  be  high. 
On  the  other  hand,  if  the  Myers  tests  were  general,  their 
inter-correlations  would  be  lowered.  Just  the  opposite  occurs ; 
the  Pintner  intercorrelations  are  lower  than  the  Myers.  These 
correlations  can  probably  be  explained  on  another  basis.  In 
the  Pintner  series  certain  tests  are  easier  than  others,  most 
esspecially  the  second  and  fourth,  which  lowers  the  intercor- 
relations. In  the  Myers  Mental  Measure  all  the  tests  with  the 
exception  of  the  third  are  of  about  the  same  difficulty,  the 
grading  being  within  the  test,  and  this  raises  the  correlations. 
It  also  seems  probable  that  while  the  Pintner  tests  do 
measure  more  limited  factors,  each  test  may  measure  a  dif- 
ferent one,  the  type  of  material  alone  remaining  the  same. 

On  a  priori  grounds  something  of  this  sort  seems  likely,  for 
the  material  is  practically  the  same,  the  correlations  are  low, 
so  the  factors  measured  must  be  different. 

It  is  true  that  in  the  Myers  Mental  Measure  the  ability  to 
respond  to  the  spoken  word  (directions)  is  part  of  the  test, 
and  it  is  possible  that  this  is  a  special  ability — calling  forth 
something  akin  to  the  abilities  necessary  for  success  with  the 
Stanford-Binet,  even  where  the  language  itself  is  easily  under- 
stood. Such  a  factor  our  data  are  unable  to  measure,  but  it 
is  interesting  in  this  connection  to  compare  the  correlation  of 
the  Stanford-Binet  with  Pintner  and  of  the  Stanford-Binet 
with  Myers. 

In  devising  the  Pintner  non-language  test,  the  effort  was 
made  to  have  it  extend  from  the  lowest  to  the  highest  grades. 
This  meant  introducing  tests  such  as  the  second,  which  is 
far  too  easy  for  a  child  after  he  has  reached  the  fourth  or 
fifth  grade,  and  also  others  which  were  almost  incompre- 
hensible to  the  young  child,  as  tests  four  and  six.  Since  our 
subjects  are  for  the  most  part  past  the  fourth  or  fifth  school 
grade,  we  would  expect  to  find  some  sign  of  their  maturity  in 
the  correlations.  Reference  to  the  table  shows  that  test  two 
correlates  lower  with  all  the  other  tests  than  any  other  single 
test.  The  one  exception  is  the  correlation  of  tests  two 
and  three,  which — it  will  be  remembered — are  identical  in 
form,  the  latter  being  different  from  the  former  only  in 
degree  of  difficulty.  Test  six,  on  the  other  hand,  correlates 
higher  with  every  other  test,  than  test  two.  This  is  as  it 
.should  be:  had  we  tested  younger  children  the  table  would 


EVALUATED  AND  COMPARED  35 

probably  have  shown  entirely  different  results.  Incidentally, 
these  findings  show  the  importance  of  bearing  in  mind  the 
nature  of  the  group  that  is  being  studied  when  interpreting 
correlations.  Each  part  was  also  correlated  with  the  total  test 
score,  with  high  results  throughout,  with  the  exception  of 
test  2.  In  looking  at  this  table,  one  must  feel  that  the  test 
is  a  good  one,  for  the  intercorrelations  of  the  separate  tests 
are  low,  but  with  the  composite  they  are  high. 

Before  leaving  the  Pintner  test,  mention  should  be  made  of 
a  study  by  Jeanette  Chase  Reamer,  in  which  she  retested 
over  four  hundred  children  with  this  test  with  slightly  less 
than  a  two-year  interval,  and  found  a  correlation  of  .726 
between  the  relative  positions  which  they  occupied  at  each 
testing.  The  closeness  of  this  correlation  was  a  complete  sur- 
prise to  both  her  and  to  Professor  Pintner. 

With  regard  to  the  Myers  Mental  Measure  intercorrelations, 
we  find  them  all  fairly  high  and  regular.  The  most  surprising 
thing  about  them  is  that  tests  three  and  four  which  appear 
far  more  similar  than  any  other  two  tests  in  this  series, 
should  have  one  of  the  lowest  correlations, — lower  than  four 
with  one  or  four  with  two.  Also,  we  see  no  reason  why  one 
and  four  should  correlate  higher  than  any  other  two.  If  the 
language  factor  were  significant,  we  should  find  one  and  three 
(where  audible  directions  must  be  followed  for  each  separate 
unit  of  the  test)  correlating  highly,  and  also  two  and  four 
(where  after  the  original  directions  the  subject  is  left  to  him- 
self). But  as  a  matter  of  fact,  one  and  two,  and  one  and 
four  are  higher  than  one  and  three,  and  two  and  four.  How- 
ever the  degree  of  difference  between  the  various  correla- 
tions is  so  small  that  these  comparisons  must  be  taken  in  a 
negative  rather  than  a  positive  sense;  that  is,  we  might  have 
expected  the  correlations  to  prove  something,  instead  of  which 
they  prove  nothing!  With  the  composite  the  separate  tests 
correlate  very  highly,  as  would  be  expected  since  the  com- 
posite includes  always  the  test  being  correlated  with  it,  thus 
giving  a  perfect  relation  between  two  out  of  the  five  factors. 
Test  three  proves  an  exception  here  also,  and  we  feel  that 
the  fault  is  the  same  as  with  Pintner  two:  it  is  too  easy  for 
our  subjects. 

The  Porteus  Maze  Test  when  correlated  with  itself  gives  a 
correlation  of  .95,  which  is  high  and  satisfactory. 

The  intercorrelations  of  the  construction  tests  gave  the 


36  SOME  WELL-KNOWN  MENTAL  TESTS 

most  disconcerting  results  of  all.  They  seem  to  prove  Pro- 
fessor Thorndike's  assertion  that  no  matter  how  many  con- 
struction tests  are  used,  one  cannot  do  away  with  the  chance 
element.  If  four  construction  tests,  when  correlated  for  time 
and  moves,  give  only  .16  for  the  former  and  .08  for  the  latter, 
it  seems  like  a  hopeless  task  to  give  sufficient  tests  to  raise 
the  correlation  to  the  high  70's  or  80's.  This  is  indeed  a 
problem,  for  the  construction  test  as  such  is  undoubtedly  de- 
sirable. 

Perhaps  more  important  than  these  low  numerical  results, 
is  the  fact  that  combining  the  individual  tests  does  not  seem 
to  operate  to  raise  the  correlations.  Thus  the  two  Healy  tests 
when  correlated  for  time,  give  a  result  of  .21,  the  two  Knox 
tests  similarly  correlated  give  .27,  but  the  average  of  Healy 
tests  with  average  of  Knox  tests  shows  a  correlation  of  only 
.16.  In  attempting  to  explain  these  findings,  it  must  be  re- 
membered that  the  Healy  tests  were  given  on  one  occasion,  and 
the  Knox  tests  at  least  one  week  later,  both  A  and  B  on  the 
same  day. 

If  our  results  were  due  primarily  to  lack  of  reliability  of 
the  construction  tests  from  day  to  day  then  scores  from  two 
construction  tests  given  on  the  same  day  ought  to  show  higher 
correlations  than  we  found.  If  the  lack  of  reliability  of  con- 
struction tests  from  day  to  day  is  not  to  be  considered  because 
of  the  generally  low  correlations,  and  so  if  it  makes  no  dif- 
ference whether  all  four  tests  are  given  on  the  same  day  or 
different  days,  then  our  average  correlations  should  not  turn 
out  to  be  lower  than  the  correlations  of  tests  given  on  the 
same  day  because  an  increase  in  the  number  of  factors  gen- 
erally operates  to  raise  the  correlations.  Other  correlations 
between  various  combinations  of  the  construction  tests  were 
made  and  are  recorded  in  table  16,  but  the  results  are  no 
more  enlightening  than  the  ones  we  have  discussed  here. 

We  are  assuming  here  that  the  solution  of  each  of  the  four 
construction  tests  involves  the  same  abilities,  not  that  they 
are  of  equal  difficulty.  We  have  no  evidence  to  prove  that 
this  is  the  case,  but  we  do  not  see  how  any  construction  tests 
could  be  devised  which,  though  different,  were  apparently 
more  similar  than  these.  However,  Healy  test  A  and  Knox 
test  B  are  more  similar  than  any  other  combination.  Knox's 
test  was  modelled  directly  from  Healy's  and  is  supposed  to 
be  more  difficult.    A  correlation  between  these  two  gives  us 


EVALUATED  AND  COMPARED  37 

minus  .055  for  time  and  .126  for  moves.  In  other  words,  the 
correlation  between  the  two  is  about  what  one  would  obtain  be- 
tween two  factors  having  no  relationship  to  each  other  at  all. 
If  this  is  true  of  Healy  Construction  test  A  and  the  Knox 
diamond-shaped  frame  test,  we  conclude  that  construction 
tests  have  no  constant  value  for  intelligence  testing. 

It  will  be  recalled  that  the  Thorndike  Reading  Scale,  Alpha 
2,  was  not  repeated  as  the  alternate  scales  now  available  had 
not  yet  been  published,  but  we  might  quote  Dr.  McCall's  state- 
ment to  the  effect  that  a  high  correlation  was  obtained  be- 
tween our  scale  and  the  more  recently  devised  alternate  on 
representative  subjects. 

No  correlation  was  obtained  between  two  trials  of  the 
Healy  Pictorial  Completion  test  II  because  the  number  of 
cases  who  were  retested  was  small,  about  twenty-five,  no  fur- 
ther retesting  being  done  because  the  attitude  of  the  subjects 
was  so  different  on  the  second  testing  that  the  repetition  was 
more  a  matter  of  memory  than  anything  else. 

In  repeating  this  test  a  week  or  more  after  the  first  pres- 
entation it  was  found  that  the  correct  pieces  were  again  put 
in.  Of  those  that  were  incorrect  about  half  were  the  same, 
the  other  half  being  pictures  having  about  the  same  value 
in  scoring,  so  that  the  total  score  was  very  little  altered.  It 
was  generally  slightly  increased,  rarely  lowered.  The  only 
other  test  of  this  kind  available  is  Healy's  Pictorial  Com- 
pletion test  A,  which  is  so  simple  that  almost  all  of  our  sub- 
jects would  make  perfect  scores  on  it.  The  attitude  of  the  sub- 
jects, when  this  test  was  offered  a  second  time,  was  not  good. 
The  test  appeals  because  it  is  a  new  situation  presenting  a 
problem  in  an  attractive  form.  The  second  time,  the  newness 
has  worn  off.  The  usual  response  is,  "I've  done  that  before," 
or  words  to  that  effect.  If  the  child  is  urged  to  attempt  a 
better  performance,  he  will  often  ask  in  a  surprised  tone  of 
voice,  "Didn't  I  do  it  perfectly  before?"  Even  when  one  suc- 
ceeds in  getting  a  child  to  try  again,  he  rarely  makes  any 
effort,  but  puts  in  at  once  the  pieces  selected  before  or  similar 
ones.  If  he  comments  audibly  on  his  performance,  it  runs 
something  like  this,  "Oh,  that  one, — a  book  was  missing  there ; 
where  is  it?  Here — why  there  are  two — well  it  doesn't  matter, 
it's  a  book  he  dropped."  Occasionally  one  will  notice  that  it 
does  matter,  but  even  this  is  due  largely  to  chance,  to  his 
happening  to  have  spied  two  books  this  time. 


38  SOME  WELL-KNOWN  MENTAL  TESTS 

As  a  whole  it  was  felt  that  what  was  gained  by  repeating 
this  test  in  the  way  of  establishing  its  reliability,  was  not 
equivalent  to  what  was  lost  in  the  attitude  of  the  subjects  to 
the  tests  as  a  whole.  If  repeated  at  the  very  end  of  the  test- 
ing, this  difficulty  would  be  in  part  eliminated,  but  it  was 
decided  to  omit  its  repetition  completely. 

The  reliability  of  the  Healy  and  Bronner  learning  tests 
was  not  ascertainable  as  no  alternate  series  has  been  devised, 
and  as  no  other  test  could  be  found  which  appeared  sufficiently 
similar  to  warrant  the  hypothesis  that  it  measured  the  same 
thing. 

The  tapping  test  was  repeated  in  exactly  the  same  form, 
and  showed  an  intercorrelation  of  .81  with  a  P.  E.  of  .022. 
This  we  may  consider  a  satisfactory  correlation,  showing 
that  the  test  has  a  high  degree  of  reliability. 

The  self-correlations  having  been  thus  completed  and  ana- 
lyzed, the  next  step  is  to  consider  the  intercorrelations  of  the 
tests.  Let  us  now  consider  the  correlation  of  each  test  with  the 
Stanford-Binet  mental  age.  As  all  the  tests  are  given  crude 
scores  regardless  of  age,  in  order  to  have  comparable  data, 
the  mental  age  must  be  used  instead  of  the  I.  Q. 


Number  of 
Cases 

97 

89 
106 
110 
105 
110 
112 
107 

83 
110 

88 
110 

88 
111 
103 
111 
103 

Total  number  of  tests  correlated  with  Stanford-Binet  r  = 
.5976.     Woodworth's   method   of  combining  the   results  of 

M  Av.S^-1 
several  tests  used,  Av.  r=  — (Woodworth:  Combin- 
ing the  Results  of  Several  Tests). 

The  first  column  stands  for  the  Pearson  coefficient  obtained 


TABLE 

XV 

Stanford-Binet 

(probable  error) 

Pintner 

.439 

±.055 

Myers 

.686 

±.037 

Alpha   2 

.757 

±.027 

P.  C.  II 

.541 

±.045 

Learning 

491 

±.049 

Porteus 

.536 

±.045 

Tapping 

.604 

±.040 

4    Construction 

.426 

(Time) 

±.078 

4  Construction 

.326 

(moves) 

±.097 

Healy  A 

.410 

(Time) 

±.079 

Healy  A 

.374 

(moves) 

±.092 

Healy   B 

.281 

(Time) 

±.088 

Healy  B 

.088 

(moves) 

±.105 

Knox   A 

.046 

(Time) 

±.095 

Knox  A 

.009 

(moves) 

±.099 

Knox   B 

.216 

(Time) 

±.090 

Knox   B 

.112 

(moves) 

±.098 

EVALUATED  AND  COMPARED  Z9 

2   (x.y) 
from  the  formula  r  =      ^^f — a — 5  or,  as  it  is  usually  stated, 

^  —        -^  V  -  ^  rj^Yie  P,  E.  in  this  case  means  the  probable 


divergence  of  the  true  coefficient  of  correlation  from  that 

obtained  from  a  limited  random  selection  of  cases.    The  for- 

l-r== 
mula  was  was  aT-obt.  r= .  If  the  median  deviation  of  the 

probable  divergence  is  desired  it  may  be  obtained  by  multi- 
plying the  figures  in  the  second  column  by.6754.  For  a  dis- 
cussion of  these  formulae  and  any  other  statistical  methods 
here  used,  see  E.  L.  Thorndike,  Mental  and  Social  Measur- 
ments. 

It  is  interesting  to  find  the  Alpha  test  correlating  most 
closely  with  the  Standford-Binet  of  all  the  tests  used.  It  cor- 
roborates to  some  extent  the  current  opinion  that  the  Stan- 
ford-Binet  is  largely  a  test  of  language  ability. 

The  next  highest  correlation,  that  of  the  Myers  Mental 
Measure,  is  more  difficult  to  explain.  Although  intended  as 
a  non-language  group  intelligence  test,  it  involved  more 
language  than  any  of  the  other  tests  employed.  Still  it  would 
seem  surprising  if  this  were  such  a  tremendous  factor.  It 
tends  to  indicate  the  validity  of  group  tests  as  does  also  Alpha, 
in  that  these  two  tests  were  given  to  nearly  all  of  the  subjects 
in  groups,  and  yet  correlate  more  highly  with  the  individual 
Stanford-Binet  than  any  of  the  other  tests  do,  practically  all 
of  which  were  given  individually. 

One  of  the  most  surprising  results  is  the  high  correlation 
of  tapping  with  the  Stanford-Binet.  One  would  generally 
assume  that  the  type  of  motor  ability  required  in  our  tapping 
test  had  little  to  do  with  intelligence — especially  with  older 
subjects.  Our  data  apparently  contradict  this  hypothesis, 
and  we  are  confronted  with  the  necessity  of  explaining  the 
data.  It  is  known  that  tapping  ability  increases  with  chrono- 
logical age  at  least  up  to  maturity  in  the  absence  of  tremors, 
epilepsy,  chorea  and  other  diseases  affecting  the  co-ordinat- 
ing mechanisms.  When  we  consider  that  our  subjects  were 
all  normal  and  therefor^  their  mental  ages  tended  to  increase 
with  their  chronological  ages,  and  that  all  our  cases  were 
treated  together  regardless  of  age,  it  at  once  seems  plausible 
that  we  have  here  a  spurious  correlation  due  to  increase  in 
both  scores  with  chronological  age,  rather  than  intelligence. 


40  SOME  WELL-KNOWN  MENTAL  TESTS 

We  have  therefore  correlated  tapping  with  the  Stanf ord-Binet 
I.  Q.'s,  which  represent  intelligence  regardless  of  age,  the 
coefficient  obtained  being  .069,  and  find  that  our  assumption 
is  justified. 

The  correlations  between  the  construction  tests  and 
Stanford-Binet  are  very  low,  the  only  reasonably  high 
coefficient  being  obtained  with  Healy  A.  This  correlation  was 
about  the  same  as  the  composite  of  construction  tests  with 
Stanford-Binet.  It  is  interesting  to  note  that  Healy  A  was 
the  only  construction  test  which  Professor  Terman  used  in 
his  revision  inasmuch  as  he  considered  that  one  only  to  meet 
the  requirements  sufficiently  to  be  included. 

The  remaining  tests,  Pintner,  Porteus,  Learning,  and  P. 
C.  2,  that  have  been  correlated  with  Stanford-Binet,  each 
show  a  correlation  very  close  to  .50.  This  we  consider  signifi- 
cant in  that  they  are  sufficiently  high  to  show  that  we  are 
measuring  intelligence,  restricting  that  term  to  its  generally 
used  meaning  with  reference  to  mental  testing.  In  addition 
the  coefficients  of  correlation  are  low  enough  so  that  we  may 
conclude  that  different  abilities  of  the  subjects  tested  are 
being  measured,  that  is,  the  use  of  different  tests  does  not 
result  in  a  repeated  measurement  of  the  same  abilities.  Con- 
sequently the  use  of  these  tests  in  addition  to  the  Stanford- 
Binet,  means  the  measurement  of  more  varieties  of  ability 
than  can  be  tested  by  the  Stanford-Binet  alone.  It  remains 
to  be  determined  whether  Pintner,  Porteus,  Learning,  and 
P.  C.  2  all  measure  the  same  factor  or  whether  some  if  not  all 
of  them  can  be  used  to  distinguish  special  abilities  which  the 
others  do  not  test.  The  answer  to  this  inquiry  lies  in  the 
results  obtainable  by  the  correlation  of  all  of  these  tests  with 
each  other.  These  results  are  recorded  in  Table  16  and  they 
are  results  so  unexpected  that  they  call  for  interpretation. 

Many  of  the  correlations  recorded  in  the  table  show  that  the 
importance  of  the  language  factor  has  been  overestimated  in 
dealing  with  older  school  children.  The  correlation  between 
language  and  non-language  tests  are  high  enough  to  show  that 
the  language  factor  need  not  be  avoided  to  have  a  test  which 
can  be  said  to  measure  intelligence. 

Let  us  first  consider  the  correlation  between  Myers  and 
Alpha  2;  the  former  is  supposed  to  be  a  non-language  test, 
the  latter  a  test  of  understanding  of  sentences.  If  language 
were  an  important  factor  it  would  be  hard  to  account  for  a 


EVALUATED  AND  COMPARED  41 

correlation  of  .733,  the  second  highest  obtained  aside  from  the 
self-correlations.  P.  C.  II  is  a  performance  test  dealing  with 
pictures ;  it  is  concrete  where  the  Alpha  2  deals  with  abstract 
ideas, — yet  these  two  give  a  correlation  of  .709 — likewise  un- 
questionably high.  We  have  stated  elsewhere  that  some 
language  enters  into  the  Myers  Mental  Measure,  and  that 
ability  to  respond  to  the  spoken  word  may  be  an  exceedingly 
important  factor.  If  so,  why  does  P.  C.  II  give  a  coefficient 
of  .714  with  Myers  Mental  Measure?  If  the  Myers  Mental 
Measure  is  a  non-language  test,  why  is  the  correlation  of 
Pintner,  a  thorough  going  non-language  test,  with  Myers 
lower  than  Pintner  with  Alpha  2,  a  test  involving  so  much 
language?  Again,  when  we  compare  the  correlation  of  Alpha 
2  and  Porteus— .701— with  that  of  P.  C.  II  and  Porteus— .702 
— we  are  at  a  loss  to  explain  the  similarity  in  result  unless  we 
discard  the  idea  of  the  importance  of  the  language  factor. 
For  the  Porteus  test  requires  no  language. 

One  must  not  overlook  the  importance  of  language  as  a 
handicap  in  giving  tests  to  foreigners,  etc.,  but  where  older 
school  children  are  being  tested  it  cannot  be  vital.  For  in 
order  to  succeed  in  the  higher  grammar  school  grades,  it  is 
essential  that  they  have  a  fairly  good  working  knowledge  of 
the  English  language,  and  this  is  all  that  is  needed  to  suc- 
ceed with  the  so-called  language  tests. 

Coming  to  the  selection  of  a  schedule  of  tests  we  conclude 
that: 

1.  Reading  scale  Alpha  2  should  be  included.  In  the  first 
place  because  of  its  high  correlations  with  other  tests,  the 
highest  of  any  test  with  all  the  others,  and  also  because  of 
special  considerations.  It  must  be  remembered  that  Alpha  2 
is  entirely  a  reading  and  writing  test  and  therefore  one  would 
not  expect  so  uniformly  high  a  correlation  as  exists  between 
it  and  the  other  tests  which  are  supposed  each  to  be  specially 
adapted  toward  bringing  out  certain  abilities.  The  high 
correlations  remind  us  of  Binet's  constant  contention  that 
intelligence,  broadly  speaking,  can  be  tested  by  language  tests. 
This  conclusion,  however,  does  not  imply  that  a  non-language 
test  cannot  serve  a  like  purpose.  Our  intercorrelations  show 
that  there  was  no  reason  to  avoid  language  tests  inasmuch  as 
they  correlated  highly  with  the  non-language  tests.  This  is 
interesting  in  that  the  tendency  in  devising  tests  is  towards 
making  them  language  tests.     For  causes  of  this  tendency 


42  SOME  WELL-KNOWN  MENTAL  TESTS 

we  can  ascribe  first,  the  simplicity  and  lack  of  apparatus 
inherent  in  them  and  second,  that  the  difficulty  or  ease  of  the 
test  is  far  more  readily  regulated  than  in  the  non-language 
tests.  In  scrutinizing  a  test  to  forecast  the  results  of  its 
use  our  results  seem  to  show  that  it  is  not  necessary  to  dwell 
upon  whether  or  not  the  tests  involve  the  use  of  language. 

2.  The  list  of  tests  selected  includes  both  Myers  and 
Pintner.  Myers  correlates  more  highly  with  every  other  test 
than  does  Pintner,  with  the  exception  of  their  respective  cor- 
relations with  Porteus.  As  has  been  stated,  both  of  these 
tests  are  valuable  and  in  addition  they  have  the  merit  of 
yielding  different  results. 

3.  The  intercorrelations  of  P.  C.  II  with  such  of  the  other 
tests  as  we  found  to  be  reliable  were  sufficiently  high  to  make 
us  believe  that  this  test  should  be  included  in  our  schedule 
in  spite  of  the  uncertainty  as  to  whether  it  is  reliable. 

4.  Definite  judgment  upon  the  learning  tests  should  be 
reserved  for  the  present.  Their  highest  correlation  is  un- 
der 50  and  we  have  no  evidence  that  they  are  reliable.  Before 
the  learning  tests  have  a  right  to  be  so  called  they  must  be 
shown  really  to  measure  learning  ability;  they  must  also  be 
tested  for  reliability.  It  is  a  question  whether  learning  ability 
of  a  given  individual  is  uniform  in  all  fields.  The  uniformity 
of  learning  ability  cannot  be  assumed,  for  a  mere  assumption 
as  to  the  uniformity  of  motor  ability  proved  to  be  wrong 
(See  Perrin,  An  Experimental  Study  of  Motor  Ability).  If 
learning  ability  is  found  not  to  be  so,  combining  the  various 
tests  may  operate  to  conceal  what  is  valuable  in  them. 

5.  The  tapping  test  should  be  included,  in  the  discretion  of 
the  examiner,  not  because  the  results  can  be  relied  upon  to 
indicate  intelligence  but  because  giving  this  test,  which  takes 
only  a  minute,  may  disclose  latent  defects  in  motor  control. 

In  an  attempt  to  reach  some  definite  conclusion  about  the 
construction  tests  we  have  made  many  correlations  of  different 
combinations.  Healy  A  is  the  only  test  which  gives  a  corre- 
lation as  high  as  .40  and  that  with  the  Stanford-Binet.  Nor 
does  combining  the  tests  raise  the  correlations,  for  the  four 
construction  tests  correlated  with  Stanford-Binet  give  a  result 
practically  no  higher  than  Healy  A  alone.  It  seemed  useless 
to  correlate  the  construction  tests  with  the  other  tests  when 
they  gave  such  unsatisfactory  results  with  each  other,  and 
with  the  Stanford-Binet.    We  have  no  evidence  that  these  four 


EVALUATED  AND  COMPARED  43 

tests  are  valuable  either  as  intelligence  tests,  or  for  any  other 
purpose. 

The  Porteus  test  is  one  of  the  most  interesting.  Since  no 
language  enters  into  the  test,  one  would  expect  it  to  correlate 
more  highly  with  Pintner  and  Myers  than  with  the  Stanf  ord- 
Binet  and  Alpha  2.  Just  the  opposite  occurs;  of  the  four, 
by  far  the  highest  correlation  is  with  Alpha  2.  The  cor- 
relation of  Porteus  and  P.  C.  II  is  practically  the  same.  These 
three  tests  all  seem  to  call  for  one  kind  of  ability.  Is  it  good 
judgment,  common  sense  ability,  planfulness,  deliberation, 
carefulness,  foresight,  good  apperceptions?  Probably  it  con- 
tains these  and  other  similar  traits.  It  is  the  difference  be- 
tween these  tests  which  brings  the  correlations  down  to  .70, 
and  which  causes  them  to  correlate  differently  with  the  other 
tests.  Alpha  2  and  Stanford-Binet,  both  requiring  language, 
correlate  more  highly  than  Porteus  and  Stanford-Binet,  or 
P.  C.  II  and  Stanford-Binet.  Some  other  factor  causes  Alpha 
2  and  P.  C.  II  to  correlate  considerably  higher  with  Myers 
than  Porteus  does.  There  are  always  many  traits  measured 
by  every  test,  no  matter  how  simple,  and  the  emphasis  on  the 
different  factors  is  not  always  the  same  for  the  same  test.  It 
varies  with  the  group  being  measured ;  their  age,  sex,  educa- 
tion, social  selection,  etc.  Why  does  Porteus  get  a  higher 
correlation  between  his  test  and  Binet's  than  we  do?  Partly, 
at  least,  because  he  tested  children  of  all  ages,  but  especially 
younger  ones,  whereas  ours  group  themselves  closely  about 
a  mode,  and  are  older. 

We  have  quite  a  number  of  cases  which  are  not  completely 
measured  by  either  the  Stanford-Binet  or  the  Porteus  tests; 
that  is,  they  could  probably  succeed  with  some  harder  tests  if 
they  were  given  the  opportunity,  and  this  lowers  our  corre- 
lations. The  fact  that  many  of  Porteus'  cases  were  placed 
higher  rather  than  lower  on  his  tests  than  on  the  Stanford- 
Binet  seems  to  show  that  they  tended  to  be  poorer  in  language 
ability  than  in  planfulness,  apperceptions, — whatever  one 
wishes  to  call  it.  Our  cases  on  the  other  hand  seem  to  find  no 
difficulty  with  the  language  factor.  It  is  by  comparing  the 
results  of  the  same  group  in  different  tests,  and  of  different 
groups  on  the  same  test,  that  most  can  be  learned  of  what 
the  tests  actually  do  measure.  In  this  study  we  have  the  same 
group  measured  by  many  different  tests.  We  find  our  inter- 
correlations  high  in  many  cases,  but  nowhere  so  high  that  we 


44  SOME  WELL-KNOWN  MENTAL  TESTS 

feel  that  the  tests  are  identical.  However  certain  similarities 
such  as  the  one  just  discussed  between  the  Porteus,  P.  C.  II, 
and  Alpha  2,  were  brought  to  light  by  this  method.  Differ- 
ences such  as  the  striking  one  between  Pintner  and  Myers 
have  also  been  observed.  If  different  groups  had  been  used, 
one  would  be  unable  to  draw  any  conclusions  regarding  the 
tests  for  the  groups  themselves  might  be  responsible  for  so 
many  of  the  factors.  Again  different  factors  of  the  tests  are 
brought  out  by  different  groups  as  for  instance  a  younger 
and  older  set  of  children  tested  with  the  Pintner  non-language 
survey  test  would  give  an  entirely  different  kind  of  intercor- 
relation  between  the  separate  tests.  By  this  method  we  can 
take  account  of  more  factors  and  so  interpret  our  findings 
with  greater  accuracy. 

There  is  no  evidence  that  the  P.  C.  test  measures  appercep- 
tions, that  the  learning  tests  measure  learning  ability,  that  the 
construction  tests  measure  ability  to  use  concrete  material.  On 
this  account,  and  also  because  each  involves  too  many  inci- 
dental, disturbing  factors,  none  of  these  tests  can  be  consi- 
dered adequate  measures  of  special  abilities  or  disabilities. 
Such  tests  are  much  needed,  and  should  be  constructed  so  as 
to  measure  fundamental,  underlying  differences  in  ability. 
They  must  be  correlated  with  everything  of  any  possible  im- 
portance in  order  to  ascertain  the  degree  to  which  one  ability 
is  related  to  all  others.  In  studying  memory  we  want  to  know 
how  important  a  part  it  plays  in  reasoning,  in  mechanical 
work,  etc.  We  must  learn  the  significance  of  a  good  memory 
for  every  school  study,  and  for  various  occupations.  If  dif- 
ferent kinds  of  memory  play  important  parts  in  different 
studies  and  vocations,  this  too  we  must  find  out.  It  is  a  big 
task,  perhaps  impossible  to  carry  out  at  present,  but  without 
such  information  we  are  tremendously  handicapped.  The 
taboo  of  "faculty"  psychology  has  contributed  to  lessen  activity 
along  these  lines,  for  if  you  investigate  memory  you  are 
getting  perilously  near  something  obsolete.  But  very  few 
would  deny  that  there  is  such  a  thing  as  remembering,  and  all 
study  of  memory  and  its  ramifications  has  yielded  interesting 
and  important  results. 

It  has  been  more  or  less  tacitly  assumed  in  the  past  that 
differences  in  performance  are  due  to  differences  in  the  ma- 
terial used  rather  than  to  underlying  "faculty"  differences. 
This  was  based  upon  findings  such  as  those  obtained  when 


EVALUATED  AND  COMPARED  46 

c:ooo(M«ioooouiO  o  r  <y 

P, WH4J 

&  §  °  %• 

C  >H  +J     C  pi? 

•CrHOOiHOOt-        CI  O_^03>H 

>H  ■<a' N  CO  ■*  (N  ■<*        N  ^    ^-Ut5 

rt 51^<U^ 


DO  ;3  o  Co> 

5tDcoo,HN      t-eo  S-S-S"^ 

^coioeooo»joiooo  }-*      cn^,^ 

*^  bJ  2J 
to  <u  p"75 

N+3  eu56 


5  >> 


"O 


•  lo-^t-t-     c-cgco  S  I' rt  ""^ 


S  ?C>  t-"   M   te:   g 


■_    w  THt- 


.2H 


*^     jjckoosco      oo(Mco  "^y-^S  .So 

^  g  ^  ■»  IT 

«     8  -S  MM 

£  goo  <J<J 

r>»00  00       eOi-(COCslC<l  •-:.  ►<>< 

•sjtoko      t-t-eoeoio         *  _:  o  o 

oj  o  >.  II   II   .1     •  II   II   'I  «  cs 

u 

-U05      -^t-ectoooN 

Ceo        00  Oi  O  lO  CO  00 
•£""<*        lOlOTfCONN 

asil   I   ^TT   I    I  MM 

M  ^-r  2Wb§  §  c  c.Smo5<J 

2      0>CDt-^«0^Tj4     ^  ^  fe'^^M^wWW^^ 

H        CO  00  lO  Tj<  CO  Oi  O        S         >   r;   rt  -->>>> 

MMM  >'>'>>xx  >'>>2  2 
«*&1  t:3S-ScHEHHiJQ^a^CC<D0J>> 

02  .S^^^    .  O  0)  es 


46  SOME  WELL-KNOWN  MENTAL  TESTS 

memory  was  tested.  It  was  found  that  a  good  memory  for 
logical  material  did  not  follow  from  a  good  memory  for 
nonsense;  that  being  able  to  remember  visually  presented 
facts  did  not  necessarily  indicate  ability  to  remember  what 
was  heard.  The  result  of  these  and  similar  observations  has 
been  the  development  of  tests  dealing  with  specific  types  of 
material,  or — giving  up  the  specific  side  entirely — tests  of 
general  intelligence.  Our  data  seem  to  indicate  that  real, 
underlying  differences  do  exist,  if  we  only  know  how  to  get  at 
them.  In  order  to  prove  this,  it  is  necessary  to  have  a  test 
with  omnibus  material,  all  of  which  is  designed  to  measure 
a  certain  type  of  thing.    We  shall  now  proceed  to  do  this. 


A  COMBINATION  TEST  FOR  PLANFULNESS 

The  correlations  in  table  XVI,  particularly  those  obtained 
between  Porteus,  Alpha  2,  and  P.  C.  II,  seem  to  indicate  the 
possibility  of  a  factor,  common  to  all  and  largely  determining 
the  score  on  each,  which  has  nothing  to  do  with  the  material 
employed,  that  is,  whether  a  language  or  non-language  test, 
or  the  like.  We  have  suggested  above  several  names  for  this 
factor, — good  judgment,  common  sense,  deliberation,  care- 
fulness, foresight,  good  apperceptions,  planfulness,  persis- 
tence, prudence  and  mental  alertness  in  meeting  a  new  sit- 
uation, ability  to  see  the  whole  of  a  situation  instead  of  re- 
acting to  the  most  obvious  part  of  it.  An  attempt  was  made 
to  investigate  it  more  thoroughly  by  combining  the  elements 
of  each  test  which  seemed  most  specifically  to  measure  it. 
The  selection  was  made  from  the  Porteus,  Myers,  Alpha  2, 
P.  C.  II,  and  Stanford-Binet  tests.  All  the  tests  selected 
would  require  about  twenty-five  minutes  to  perform,  this 
being  a  liberal  estimate  based  upon  the  time  limit  for  each 
test.  Alpha  2  has  no  definite  time  limit,  but  from  the  writer's 
experience,  ten  minutes  would  seem  ample  to  allow  for  the 
parts  of  the  test  included  in  this  selection.  When  all  the  in- 
dividual tests  had  been  chosen,  they  were  divided  into  two 
sections,  and  a  self-correlation  of  .763  was  obtained  with  80 
cases.    The  tests  in  each  group  were : 

I.     Porteus — year  11   (scored  0,  1,  2)  year  12   (scored  0,  1, 
2,3,4). 

Myers — pages  4.   Numbers  3  and  7  (scored  each  0,  1). 
P.  C.  II — pictures  2  and  6  (scored  1  each  if  OK;  other- 
wise 0). 
Alpha  2,  Part  II — difficulty  8 — number  4   (scored  0,  1). 

Pintner — test  5,  numbers  5  and  7  (scored  each  0,  1). 

Pintner — test  6,  picture  2  pieces  2  and  1   (scored  each 
0,1). 

Pintner — test  6,  picture  3,  pieces  4  and  1  (scored  each  0, 

1). 


II.    Porteus — year  10  (scored  0,  1,  2)  year  14  (scored  0,  1, 
2,3,4). 

47 


48  SOME  WELL-KNOWN  MENTAL  TESTS 

Myers — page  4.  Numbers  5  and  10  (scored  each  0,  1). 
P.  C.  II — pictures  7  and  8  (scored  1  each  if  OK;  otherwise 
0). 

Alpha  2,  Part  II — difficulty  8 — number  1   (scored  0,  1). 
Pintner — test  5,  number  6  (scored  0,  1). 
Pintner — test  6,  picture  2,  pieces  4  and  3   (scored  each 
0,  1). 

Pintner — ^test  6,  picture  3,  pieces  2  and  3   (scored  each 
0,1). 
Stanford-Binet — XIV  years,  number  6  (scored  0,  1). 


The  Porteus  tests  were  chosen  because  they  were  devised 
to  measure  this  very  thing.  The  fact  that  only  one  type  of 
material — mazes — was  included,  was  considered  by  Porteus 
one  of  the  outstanding  advantages  of  his  test.  We  feel  that 
this  is  a  disadvantage  since  some  children  might  have  a  dis- 
ability for  working  with  this  kind  of  material  although 
possessed  of  common  sense,  foresight,  etc.  With  omnibus 
material  this  special  factor  is  overcome.  The  choice  of  the 
four  most  difficut  tests  was  largely  a  matter  of  the  distri- 
bution of  the  subjects.  Too  many  would  have  made  perfect 
records  on  the  easier  tests. 

The  selection  from  Myers  Mental  Measure  was  based  largely 
upon  resistance  to  suggestion.  In  each  case  four  pictures 
with  some  element  in  common  must  be  chosen  from  eight 
possible  ones  and  underlined.  These  four  could  not  be  too 
difficult  or  our  subjects  would  all  score  0;  if  they  were  too 
easy  we  would  have  no  reason  to  believe  that  this  characteris- 
tic pertained  to  them.  Number  3  is  the  selection  of  four  toys, 
— a  tricycle,  top,  kite  and  rocking  horse,  vdth  a  soldier  as  the 
confusing  picture.  In  number  5,  four  items  made  of  iron  must 
be  chosen, — a  stove,  dagger,  or  sword,  train,  and  lock.  This 
has  several  confusing  suggestions.  There  is  a  broom  which 
might  be  associated  with  the  stove,  and  two  animals  which 
might  be  connected  with  the  train  as  they  all  are  capable  of 
locomotion.  Number  7  consists  of  an'  insect,  a  broom,  a  bird, 
a  table,  a  butterfly,  an  aeroplane,  a  goat  and  a  cow.  The 
four  things  which  can  travel  in  air  are  to  be  underlined.  The 
two  animals  prove  confusing  to  many  children.  In  number 
10  the  subject  is  to  select  four  articles  of  wood, — two  trees,  a 
barrel  and  a  table,  with  a  snake,  a  camel,  a  cannon,  and  a 


EVALUATED  AND  COMPARED  49 

bird  to  be  omitted.  Here  also  the  three  animals  receive  con- 
siderable attention,  the  hasty  child  not  noticing  that  the  fourth 
is  lacking,  or  the  snake  is  overlooked,  the  two  remaining 
animals  and  two  trees  being  classed  together  as  objects 
possessing  life.  There  seems  to  be  some  suggestion  in  each 
of  these  pictures,  and  it  is  certainly  true  that  a  careful, 
deliberate,  performance  by  a  subject  who  takes  in  the  whole 
situation  and  responds  to  it  will  give  far  better  results  than 
a  hasty,  careless  one. 

The  pictures  from  P.  C.  II  are  those  in  which  there  are 
several  obvious  possibilities.  A  hasty,  careless  selection  will 
hit  upon  the  first  possible  one,  rather  than  searching  further 
for  the  exactly  correct  one.  All  correct  pieces  were  checked 
by  asking  the  subject  why  that  particular  one  had  been  chosen 
and  if  it  was  put  in  by  chance,  no  credit  was  given.  The 
partial  credits  given  by  Healy  were  omitted,  the  picture 
scored  either  as  perfect  or  a  failure.  This  was  necessary  in 
order  to  eliminate  the  other  possible  factors  which  enter  into 
solving  the  test  partly.  For  instance,  in  the  second  picture, 
where  a  book  is  missing,  it  is  not  sufficient  to  put  in  any  book, 
pencil  case  or  lunch  box,  but  by  following  up  persistently  all 
the  clues,  the  one  and  only  correct  red  book  can  be  placed  in 
the  space  with  certainty. 

From  the  Thorndike  Alpha  2  reading  scale  questions  were 
selected  which  had  been  answered  by  a  large  number  of 
children.  Question  I  requires  a  fairly  careful  study  of  the 
paragraph  in  order  to  find  just  what  it  is  that  seems  true  at 
first  but  is  really  false.  The  question  is  a  little  clumsily  put, — 
certainly  not  direct  and  to  the  point, — which  is  an  advantage 
for  our  purposes.  Question  4  is  not  a  reading  scale  problem 
proper,  but  necessitates  close  attention  to  several  directions. 
In  two  rows  of  digits  the  subject  must  underline  every  five 
that  comes  just  after  a  two,  unless  the  two  comes  just  after 
a  nine.  If  that  is  the  case,  he  must  draw  a  line  under  the 
next  figure  after  the  five.  The  last  few  lines  of  the 
first  page  of  the  Myers  Mental  Measure  are  similar  to  this, 
but  the  Alpha  2  was  given  to  a  larger  number  of  cases,  there 
was  no  time  limit,  and  less  possibility  of  copying,  so  it  was 
given  the  preference,  as  being  more  accurate. 

Numbers  5,  6,  and  7  from  Pintner  test  5  are  all  similar  in 
nature.  Given  a  drawing,  the  problem  is  to  draw  it  in  a 
reversed  position,  with  two  lines  of  the  second  position  given 


50  SOME  WELL-KNOWN  MENTAL  TESTS 

on  which  to  construct  the  rest.  This  seems  like  a  rather 
special  ability,  but  Pintner  gives  each  drawing  considerable 
weight  in  his  total  score,  and  persistence  and  planfulness  are 
certainly  essential  for  a  good  performance. 

Pintner  test  6  consists  of  parts  of  pictures  presented  in  a 
disarranged  order.  Each  part  is  numbered  and  blank  spaces 
are  provided  in  which  the  subject  is  to  place  the  numbers  of 
the  parts  in  order  which  would  give  a  perfect  ensemble.  Here 
again  planfuness,  patience,  and  foresight  are  needed,  and  on 
the  whole  the  subject  who  possesses  them  to  the  greatest 
degree  will  be  the  most  successful. 

Finally  one  test  was  selected  from  the  Stanf ord-Binet  scale, 
— namely  the  reversed  clock  hands  of  year  XIV.  If  two  out  of 
three  were  correct  a  score  of  one  was  given,  if  less  no  credit  at 
all.  This  test  seemed  to  require  the  same  kind  of  ability  as 
many  of  the  other  tests  included,  and  was  therefore  added. 
Some  of  the  other  Stanf  ord-Binet  series  might  have  been  used 
also,  but  those  which  seemed  desirable  came  too  high  or  too 
low  in  the  scale  so  that  the  distribution  for  our  subjects  would 
not  be  satisfactory. 

The  correlation  of  .763  obtained  between  the  two  parts  is 
fairly  high  when  it  is  remembered  that  the  highest  score  on 
each  section  can  only  be  17 ;  also  that  the  whole  series  of  both 
parts  would  only  take  half  an  hour  to  give.  As  to  reliability 
it  is  a  noteworthy  conclusion  that  this  self-correlation  is  the 
highest  one  obtained  with  any  non-identical  material.  A 
correlation  of  the  composite  tests  with  any  of  the  tests  which 
are  included  would  probably  give  a  high  coefficient  difficult 
to  interpret  because  of  the  varying  amount  of  each  included 
in  the  composites,  and  a  low  correlation  with  learning  tests, 
construction  tests,  or  tapping  could  hardly  be  considered 
strong  evidence  in  favor  of  our  new  grouping.  But  the 
correlation  with  Stanford-Binet  seemed  worth  finding,  and 
when  worked  out  yielded  a  coefficient  of  .537.  This  indicates 
that  our  combination  test  is  comparable  with  the  whole  series 
of  tests  from  which  it  was  compiled.  We  have,  however,  no 
criterion  to  prove  that  it  actually  measures  the  trait  which  we 
presuppose  it  does.  But  this  same  criticism  applies  to  all  the 
tests  which  are  supposed  to  measure  specific  factors.  Our 
new  test  combination  of  old  material  is  certainly  as  good  as 
the  tests  from  which  it  originated;  we  think  it  is  better,  be- 
cause it  gives  evidence  of  measuring  one  trait,  or  group  of 


EVALUATED  AND  COMPARED  51 

traits  with  a  variety  of  materials,  whereas  all  the  others 
measure  many  kinds  of  traits  with  identical  or  similar  ma- 
terial. That  is,  the  classification  and  material  preparatory 
to  the  formation  of  a  test  has  generally  heretofore  been  along 
the  lines  of  the  material  employed,  such  as  form  boards,  etc., 
whereas  the  combination  test  being  discussed  presents  the 
results  obtained  from  forming  a  test  directed  toward  plan- 
fulness,  or  other  ability. 


CONCLUSION 

It  is  proposed  to  set  forth  the  practical  results  of  this  study, 
to  show  the  positive  information  that  has  been  ascertained 
and  also  to  show  from  the  experience  gathered  in  the  course 
of  obtaining  such  information,  what  further  investigations 
should  be  made,  with  what  purpose,  and  what  methods  may- 
lead  to  success.  This  study  has  reached  some  positive  results 
and  has  disclosed  other  perhaps  more  valuable  ones  in  the 
same  field. 

In  entering  upon  this  study  it  was  believed  that  the  results 
of  the  method  that  has  been  pursued  would  justify  the  con- 
clusion that  the  Stanford-Binet  series  can  be  used  as  a  test  of 
general  intelligence  and  that  certain  other  tests  used  as  auxili- 
aries would  make  apparent  and  give  a  measure  of  special 
abilities  not  individually  measured  by  the  Stanford-Binet. 
It  was  expected  that  the  various  tests  would  give  reasonably 
high  correlations  with  the  Stanford-Binet  and  rather  low 
correlations  with  each  other,  thue  on  the  one  hand  establishing 
the  reliability  of  the  tests  used,  and  on  the  other  hand,  the 
diversity  of  the  abilities  that  were  subjected  to  measurement. 

These  results  were  anticipated  because  care  was  used  in 
selecting  the  tests  to  take  those  which  had  an  approved  author- 
ship, an  extended  use,  a  definite  purpose,  and  a  general  repu- 
tation of  success  in  the  field  they  purported  to  cover.  That 
is,  the  various  units  had  each  been  shown  apparently  to  be 
satisfactory  and  on  these  a  priori  grounds  it  was  thought 
that  properly  selected  units  used  in  conjunction  would  result 
in  a  reliable  schedule. 

Had  the  results  of  the  correlations  been  in  harmony  with 
this  anticipated  situation,  we  might  properly  have  pointed  to 
this  study  as  a  demonstration  of  the  process  by  which  sched- 
ules of  tests  for  children  should  be  composed. 

Looking  upon  our  results  as  they  have  been  reported  upon, 
the  fact  is  obvious  that  there  is  no  such  easy  manner  in  which 
to  arrive  at  reliable  schedules  of  tests.  Unexpected  low  cor- 
relations were  obtained  in  some  situations  where  the  indicated 
results  should  have  been  high,  and  vice  versa,  and  while  our 
positive  purpose  therefore  met  with  disappointing  obstacles, 
a  study  of  the  figures  as  we  have  them  led  to  other  worth- 
while conclusions. 

62 


EVALUATED  AND  COMPARED  53 

Drawing  upon  the  results  of  the  correlations,  it  can  be 
stated  with  assurance  that  it  will  not  be  well  to  take  tests 
upon  which  a  high  face  value  has  been  placed  when  they  were 
used  without  being  effectively  valued  by  comparison,  and 
combining  a  number  of  them  in  the  expectation  of  using  the 
combination  to  get  reliable  information  as  to  the  general 
intelligence  and  the  special  abilities  of  normal  children.  One 
of  the  best  examples  which  we  can  show,  as  a  result  of  this 
study,  of  the  impropriety  of  such  procedure  is,  that  the  type 
of  material  used  does  not  govern  the  abilities  tested.  We 
obtained  a  higher  correlation  between  a  language  and  a  non- 
language  test  than  between  two  language  tests  or  two  non- 
language  tests,  similar  examples  can  be  drawn  from  the  corre- 
lations listed  above  respecting  other  characteristics  of  various 
tests.  Insofar  therefore  as  authors  of  tests  have  relied  upon 
the  material  as  a  quality  that  would  single  out  and  measure  a 
certain  one  of  many  abilities,  it  seems  clear  that  individual 
tests  miss  their  purpose.  However,  the  correlations  did  seem 
to  show  that  something  definite  was  being  tested,  so  that 
if  our  purpose  of  finding  a  schedule  of  tests  at  once  sufficient 
to  measure  both  general  and  special  abilities,  was  disap- 
pointed, at  least  the  schedule  we  used  can  be  relied  upon  for 
general  abilities  and  that  such  a  schedule  is  more  reliable  than 
the  Stanford-Binet  alone.  The  components  of  this  schedule 
have  been  previously  listed  and  it  only  remains  to  state  what 
individual  matters  of  interest  relating  to  each  were  made 
clear  in  the  course  of  the  study  which  was  directed  to  larger 
purposes. 

It  was  a  matter  of  actual  demonstration  herein  that  all 
of  the  construction  tests  used  are  unreliable,  this  conclusion 
disproving  the  previously  held  opinion  based  upon  empirical 
considerations  to  the  effect  that  they  reliably  measure  ability 
to  handle  concrete  material. 

Persons  having  occasion  to  apply  mental  tests  have  too 
frequently  overlooked  the  matter  of  how  far  the  test  can  be 
relied  upon.  This  is  an  important  matter  and  consequently 
it  should  be  of  some  interest  to  note  that  the  reliability  of  the 
Stanford-Binet,  Pintner  non-language  group  test,  Thorndike 
reading  scale  Alpha  2,  Porteus  Maze  Test,  and  tapping  test 
has  been  established,  whereas  the  Myers  Mental  Measure, 
the  Healy  Pictorial  Completion  test  II,  the  Healy-Bronner 


54  SOME  WELL-KNOWN  MENTAL  TESTS 

learning  tests  and  the  crossline  tests  are  not  yet  definitely 
shown  to  be  reliable. 

Care  should  also  be  observed  in  interpreting  the  results  of 
correlations,  for  the  mere  fact  of  high  correlation  is  only 
generally  and  not  conclusively  proof  of  reliability.  There  is 
the  possibility  that  factors  causing  unreliability  have  been 
hidden — thus,  in  the  tapping  test,  the  high  correlation  with 
Stanford-Binet  was  deceptive  owing  to  the  fact  that  the 
scores  on  both  increased  with  the  age  of  the  subjects.  Other 
specific  remarks  relating  to  individual  tests  are  contained  in 
the  results. 

There  remains  to  state  what  considerations  we  have  found 
to  have  a  probable  value  as  to  future  work  in  this  field.  If 
we  found  on  the  one  hand  that  the  type  of  material  used  in 
a  test  does  not  govern  the  ability  tested,  on  the  other  hand 
there  are  some  indications  that  to  test  individual  abilities  the 
test  should  have  a  variety  of  material.  So  far  the  elements 
of  a  desired  test  can  be  stated,  but  the  further  necessity  of 
finding  just  what  material  is  suitable,  can  only  be  determined 
by  practical  work  consisting  of  correlation  with  outside 
criteria  and  with  any  other  measures  of  claimed  effectiveness 
in  the  field  in  question. 

As  an  experimental  example,  for  the  confines  of  this  study 
would  allow  no  more  extended  investigation,  various  parts  of 
a  number  of  the  tests  were  united  in  a  combination  test  in- 
tended to  secure  a  measure  of  planfulness.  The  resulting 
correlations  indicated  success  in  this  attempt.  A  similar  or 
even  greater  measure  of  success  may  follow  further  com- 
binations aimed  at  the  measurement  of  other  abilities. 

It  may  also  be  stated  as  having  been  illustrated  in  the  course 
of  this  study  that  the  supposed  merit  of  various  mental  tests 
based  upon  various,  insufficient  or  unscientific  criteria,  such 
as  mere  hypothesis,  or  even  practical  results,  if  relied  upon, 
may  lead  to  misleading  or  dangerous  conclusions,  and  that 
before  one  takes  the  responsibility  of  giving  advice  or  of 
taking  action  with  respect  to  information  gained  from  the  ap- 
plication of  mental  tests,  there  should  be  available  the  as- 
surance that  proper  comparative  tests  and  correlations  have 
verified  the  supposed  propriety  of  relying  upon  the  results. 


w 


.w 


VITA 

The  author  of  this  dissertation  was  born  in  New  York,  August  25,  1898. 
Secondary  education  was  at  Far  Rockaway  High  School,  taking  highest 
honors,  and  receiving  Regents  Scholarship  for  College.  Vassar  College, 
1915-1917;  Barnard  College,  Columbia  University,  1917-1919;  B.  A.  De- 
gree Columbia  University,  1919,  Honors  in  Psychology;  1918,  research 
work  for  New  Jersey  State  Institution  for  Feeble  Minded;  1919-1920, 
Fellowship  at  Judge  Baker  Foundation,  Boston,  Assistant  Psychologist; 
Columbia  University,  1920-1922,  Post  Graduate  Work  in  Psychology. 


T'X 


THIS  BOOK  IS  DUE  ON  THE  LAST  DATE 
STAMPED  BELOW 


AN  INITIAL  FINE  OF  25  CENTS 

WILL  BE  ASSESSED  FOR  FAILURE  TO  RETURN 
THIS  BOOK  ON  THE  DATE  DUE.  THE  PENALTY 
WILL  INCREASE  TO  50  CENTS  ON  THE  FOURTH 
DAY     AND     TO     $1.00     ON     THE     SEVENTH     DAY 

°^^^^ •       Jun7'47PW 


nf^c 


21  H.i 


JUN    9  ifiy: 


■^^^ 


Pro  2^ 


m? 


Duppr-?.-r"'' 


affi'DJJ)   »«R2l72-KflM31 


•"i8'«:  a 


LD  21-100/n-7,'39(402s 


m 
m 


5n77r,3 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 


